diff --git a/src/tint/utils/string_stream.h b/src/tint/utils/string_stream.h
index 67a339391b..6cb6efcd3b 100644
--- a/src/tint/utils/string_stream.h
+++ b/src/tint/utils/string_stream.h
@@ -103,10 +103,6 @@ class StringStream {
     /// @returns the string contents of the stream
     std::string str() const { return sstream_.str(); }
 
-    /// [DEPRECATED] This should not be called.
-    /// @returns the underlying stream
-    std::ostream& stream() { return sstream_; }
-
   private:
     std::stringstream sstream_;
 };
diff --git a/src/tint/writer/glsl/generator_impl.cc b/src/tint/writer/glsl/generator_impl.cc
index 199990a5ab..46428b051a 100644
--- a/src/tint/writer/glsl/generator_impl.cc
+++ b/src/tint/writer/glsl/generator_impl.cc
@@ -381,7 +381,7 @@ bool GeneratorImpl::EmitBitcast(utils::StringStream& out, const ast::BitcastExpr
             return false;
         }
     }
-    ScopedParen sp(out.stream());
+    ScopedParen sp(out);
     if (!EmitExpression(out, expr->expr)) {
         return false;
     }
@@ -425,7 +425,7 @@ bool GeneratorImpl::EmitVectorRelational(utils::StringStream& out,
         default:
             break;
     }
-    ScopedParen sp(out.stream());
+    ScopedParen sp(out);
     if (!EmitExpression(out, expr->lhs)) {
         return false;
     }
@@ -445,14 +445,14 @@ bool GeneratorImpl::EmitBitwiseBoolOp(utils::StringStream& out, const ast::Binar
                   "")) {
         return false;
     }
-    ScopedParen outerCastParen(out.stream());
+    ScopedParen outerCastParen(out);
     // Cast LHS to uint scalar or vector type.
     if (!EmitType(out, uint_type, builtin::AddressSpace::kUndefined, builtin::Access::kReadWrite,
                   "")) {
         return false;
     }
     {
-        ScopedParen innerCastParen(out.stream());
+        ScopedParen innerCastParen(out);
         // Emit LHS.
         if (!EmitExpression(out, expr->lhs)) {
             return false;
@@ -473,7 +473,7 @@ bool GeneratorImpl::EmitBitwiseBoolOp(utils::StringStream& out, const ast::Binar
         return false;
     }
     {
-        ScopedParen innerCastParen(out.stream());
+        ScopedParen innerCastParen(out);
         // Emit RHS.
         if (!EmitExpression(out, expr->rhs)) {
             return false;
@@ -532,7 +532,7 @@ bool GeneratorImpl::EmitFloatModulo(utils::StringStream& out, const ast::BinaryE
     // Call the helper
     out << fn;
     {
-        ScopedParen sp(out.stream());
+        ScopedParen sp(out);
         if (!EmitExpression(out, expr->lhs)) {
             return false;
         }
@@ -592,7 +592,7 @@ bool GeneratorImpl::EmitBinary(utils::StringStream& out, const ast::BinaryExpres
         return EmitFloatModulo(out, expr);
     }
 
-    ScopedParen sp(out.stream());
+    ScopedParen sp(out);
     if (!EmitExpression(out, expr->lhs)) {
         return false;
     }
@@ -731,7 +731,7 @@ bool GeneratorImpl::EmitFunctionCall(utils::StringStream& out,
     auto* ident = fn->Declaration()->name;
 
     out << builder_.Symbols().NameFor(ident->symbol);
-    ScopedParen sp(out.stream());
+    ScopedParen sp(out);
 
     bool first = true;
     for (auto* arg : args) {
@@ -813,7 +813,7 @@ bool GeneratorImpl::EmitBuiltinCall(utils::StringStream& out,
     }
 
     out << name;
-    ScopedParen sp(out.stream());
+    ScopedParen sp(out);
 
     bool first = true;
     for (auto* arg : call->Arguments()) {
@@ -837,7 +837,7 @@ bool GeneratorImpl::EmitValueConversion(utils::StringStream& out,
                   builtin::Access::kReadWrite, "")) {
         return false;
     }
-    ScopedParen sp(out.stream());
+    ScopedParen sp(out);
 
     if (!EmitExpression(out, call->Arguments()[0]->Declaration())) {
         return false;
@@ -860,7 +860,7 @@ bool GeneratorImpl::EmitValueConstructor(utils::StringStream& out,
     if (!EmitType(out, type, builtin::AddressSpace::kUndefined, builtin::Access::kReadWrite, "")) {
         return false;
     }
-    ScopedParen sp(out.stream());
+    ScopedParen sp(out);
 
     bool first = true;
     for (auto* arg : call->Arguments()) {
@@ -883,7 +883,7 @@ bool GeneratorImpl::EmitWorkgroupAtomicCall(utils::StringStream& out,
     auto call = [&](const char* name) {
         out << name;
         {
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
             for (size_t i = 0; i < expr->args.Length(); i++) {
                 auto* arg = expr->args[i];
                 if (i > 0) {
@@ -903,7 +903,7 @@ bool GeneratorImpl::EmitWorkgroupAtomicCall(utils::StringStream& out,
             // atomicOr using 0 as the OR value
             out << "atomicOr";
             {
-                ScopedParen sp(out.stream());
+                ScopedParen sp(out);
                 if (!EmitExpression(out, expr->args[0])) {
                     return false;
                 }
@@ -1101,7 +1101,7 @@ bool GeneratorImpl::EmitSelectCall(utils::StringStream& out, const ast::CallExpr
         out << ")";
         return true;
     }
-    ScopedParen paren(out.stream());
+    ScopedParen paren(out);
     if (!EmitExpression(out, expr_cond)) {
         return false;
     }
@@ -1182,7 +1182,7 @@ bool GeneratorImpl::EmitDotCall(utils::StringStream& out,
     }
 
     out << fn;
-    ScopedParen sp(out.stream());
+    ScopedParen sp(out);
 
     if (!EmitExpression(out, expr->args[0])) {
         return false;
@@ -1378,7 +1378,7 @@ bool GeneratorImpl::EmitTextureCall(utils::StringStream& out,
             return EmitExpression(out, e);
         }
         emit_signed_int_type(ty);
-        ScopedParen sp(out.stream());
+        ScopedParen sp(out);
         return EmitExpression(out, e);
     };
 
@@ -1388,7 +1388,7 @@ bool GeneratorImpl::EmitTextureCall(utils::StringStream& out,
             // textureSize() / imageSize() returns a signed scalar / vector in GLSL.
             // Cast.
             emit_unsigned_int_type(call->Type());
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
 
             if (texture_type->Is<type::StorageTexture>()) {
                 out << "imageSize(";
@@ -1427,7 +1427,7 @@ bool GeneratorImpl::EmitTextureCall(utils::StringStream& out,
             // textureSize() / imageSize() returns a signed scalar / vector in GLSL.
             // Cast.
             out << "uint";
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
 
             if (texture_type->Is<type::StorageTexture>()) {
                 out << "imageSize(";
@@ -1461,7 +1461,7 @@ bool GeneratorImpl::EmitTextureCall(utils::StringStream& out,
             // textureQueryLevels() returns a signed scalar in GLSL.
             // Cast.
             out << "uint";
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
 
             out << "textureQueryLevels(";
             if (!EmitExpression(out, texture)) {
@@ -1475,7 +1475,7 @@ bool GeneratorImpl::EmitTextureCall(utils::StringStream& out,
             // textureSamples() returns a signed scalar in GLSL.
             // Cast.
             out << "uint";
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
 
             out << "textureSamples(";
             if (!EmitExpression(out, texture)) {
@@ -2367,7 +2367,7 @@ bool GeneratorImpl::EmitConstant(utils::StringStream& out, const constant::Value
                 return false;
             }
 
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
 
             if (constant->AllEqual()) {
                 return EmitConstant(out, constant->Index(0));
@@ -2389,7 +2389,7 @@ bool GeneratorImpl::EmitConstant(utils::StringStream& out, const constant::Value
                 return false;
             }
 
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
 
             for (size_t column_idx = 0; column_idx < m->columns(); column_idx++) {
                 if (column_idx > 0) {
@@ -2407,7 +2407,7 @@ bool GeneratorImpl::EmitConstant(utils::StringStream& out, const constant::Value
                 return false;
             }
 
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
 
             auto count = a->ConstantCount();
             if (!count) {
@@ -2434,7 +2434,7 @@ bool GeneratorImpl::EmitConstant(utils::StringStream& out, const constant::Value
 
             out << StructName(s);
 
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
 
             for (size_t i = 0; i < s->Members().Length(); i++) {
                 if (i > 0) {
@@ -2499,7 +2499,7 @@ bool GeneratorImpl::EmitZeroValue(utils::StringStream& out, const type::Type* ty
                       "")) {
             return false;
         }
-        ScopedParen sp(out.stream());
+        ScopedParen sp(out);
         for (uint32_t i = 0; i < vec->Width(); i++) {
             if (i != 0) {
                 out << ", ";
@@ -2513,7 +2513,7 @@ bool GeneratorImpl::EmitZeroValue(utils::StringStream& out, const type::Type* ty
                       "")) {
             return false;
         }
-        ScopedParen sp(out.stream());
+        ScopedParen sp(out);
         for (uint32_t i = 0; i < (mat->rows() * mat->columns()); i++) {
             if (i != 0) {
                 out << ", ";
@@ -2528,7 +2528,7 @@ bool GeneratorImpl::EmitZeroValue(utils::StringStream& out, const type::Type* ty
             return false;
         }
         bool first = true;
-        ScopedParen sp(out.stream());
+        ScopedParen sp(out);
         for (auto* member : str->Members()) {
             if (!first) {
                 out << ", ";
@@ -2542,7 +2542,7 @@ bool GeneratorImpl::EmitZeroValue(utils::StringStream& out, const type::Type* ty
                       "")) {
             return false;
         }
-        ScopedParen sp(out.stream());
+        ScopedParen sp(out);
 
         auto count = arr->ConstantCount();
         if (!count) {
@@ -3111,7 +3111,7 @@ bool GeneratorImpl::EmitUnaryOp(utils::StringStream& out, const ast::UnaryOpExpr
             break;
     }
 
-    ScopedParen sp(out.stream());
+    ScopedParen sp(out);
     if (!EmitExpression(out, expr->expr)) {
         return false;
     }
@@ -3243,7 +3243,7 @@ bool GeneratorImpl::CallBuiltinHelper(utils::StringStream& out,
     // Call the helper
     out << fn;
     {
-        ScopedParen sp(out.stream());
+        ScopedParen sp(out);
         bool first = true;
         for (auto* arg : call->args) {
             if (!first) {
diff --git a/src/tint/writer/hlsl/generator_impl.cc b/src/tint/writer/hlsl/generator_impl.cc
index 0d628e795b..2bb4a9f0ca 100644
--- a/src/tint/writer/hlsl/generator_impl.cc
+++ b/src/tint/writer/hlsl/generator_impl.cc
@@ -757,7 +757,7 @@ bool GeneratorImpl::EmitBinary(utils::StringStream& out, const ast::BinaryExpres
         return true;
     }
 
-    ScopedParen sp(out.stream());
+    ScopedParen sp(out);
 
     if (!EmitExpression(out, expr->lhs)) {
         return false;
@@ -1419,7 +1419,7 @@ bool GeneratorImpl::EmitStorageBufferAccess(
                 if (n > 1) {
                     out << n;
                 }
-                ScopedParen sp(out.stream());
+                ScopedParen sp(out);
                 if (!EmitExpression(out, offset)) {
                     return false;
                 }
@@ -1433,7 +1433,7 @@ bool GeneratorImpl::EmitStorageBufferAccess(
             // to emit `buffer.Load<float16_t>(offset)`.
             auto templated_load = [&](const char* type) {
                 out << buffer << ".Load<" << type << ">";  // templated load
-                ScopedParen sp(out.stream());
+                ScopedParen sp(out);
                 if (!EmitExpression(out, offset)) {
                     return false;
                 }
@@ -1485,12 +1485,12 @@ bool GeneratorImpl::EmitStorageBufferAccess(
                 if (n > 1) {
                     out << n;
                 }
-                ScopedParen sp1(out.stream());
+                ScopedParen sp1(out);
                 if (!EmitExpression(out, offset)) {
                     return false;
                 }
                 out << ", asuint";
-                ScopedParen sp2(out.stream());
+                ScopedParen sp2(out);
                 if (!EmitExpression(out, value)) {
                     return false;
                 }
@@ -1501,7 +1501,7 @@ bool GeneratorImpl::EmitStorageBufferAccess(
             // to emit `buffer.Store<float16_t>(offset)`.
             auto templated_store = [&](const char* type) {
                 out << buffer << ".Store<" << type << ">";  // templated store
-                ScopedParen sp1(out.stream());
+                ScopedParen sp1(out);
                 if (!EmitExpression(out, offset)) {
                     return false;
                 }
@@ -1849,7 +1849,7 @@ bool GeneratorImpl::EmitWorkgroupAtomicCall(utils::StringStream& out,
 
             out << "InterlockedExchange";
             {
-                ScopedParen sp(out.stream());
+                ScopedParen sp(out);
                 if (!EmitExpression(out, expr->args[0])) {
                     return false;
                 }
@@ -1944,7 +1944,7 @@ bool GeneratorImpl::EmitSelectCall(utils::StringStream& out, const ast::CallExpr
     auto* expr_false = expr->args[0];
     auto* expr_true = expr->args[1];
     auto* expr_cond = expr->args[2];
-    ScopedParen paren(out.stream());
+    ScopedParen paren(out);
     if (!EmitExpression(out, expr_cond)) {
         return false;
     }
@@ -3312,7 +3312,7 @@ bool GeneratorImpl::EmitConstant(utils::StringStream& out,
         [&](const type::Vector* v) {
             if (constant->AllEqual()) {
                 {
-                    ScopedParen sp(out.stream());
+                    ScopedParen sp(out);
                     if (!EmitConstant(out, constant->Index(0), is_variable_initializer)) {
                         return false;
                     }
@@ -3329,7 +3329,7 @@ bool GeneratorImpl::EmitConstant(utils::StringStream& out,
                 return false;
             }
 
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
 
             for (size_t i = 0; i < v->Width(); i++) {
                 if (i > 0) {
@@ -3347,7 +3347,7 @@ bool GeneratorImpl::EmitConstant(utils::StringStream& out,
                 return false;
             }
 
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
 
             for (size_t i = 0; i < m->columns(); i++) {
                 if (i > 0) {
@@ -3507,7 +3507,7 @@ bool GeneratorImpl::EmitValue(utils::StringStream& out, const type::Type* type,
                           "")) {
                 return false;
             }
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
             for (uint32_t i = 0; i < vec->Width(); i++) {
                 if (i != 0) {
                     out << ", ";
@@ -3523,7 +3523,7 @@ bool GeneratorImpl::EmitValue(utils::StringStream& out, const type::Type* type,
                           "")) {
                 return false;
             }
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
             for (uint32_t i = 0; i < (mat->rows() * mat->columns()); i++) {
                 if (i != 0) {
                     out << ", ";
@@ -4382,7 +4382,7 @@ bool GeneratorImpl::CallBuiltinHelper(utils::StringStream& out,
     // Call the helper
     out << fn;
     {
-        ScopedParen sp(out.stream());
+        ScopedParen sp(out);
         bool first = true;
         for (auto* arg : call->args) {
             if (!first) {
diff --git a/src/tint/writer/msl/generator_impl.cc b/src/tint/writer/msl/generator_impl.cc
index 2fcda2dc88..81b32c04e3 100644
--- a/src/tint/writer/msl/generator_impl.cc
+++ b/src/tint/writer/msl/generator_impl.cc
@@ -525,7 +525,7 @@ bool GeneratorImpl::EmitBinary(utils::StringStream& out, const ast::BinaryExpres
     // Handle fmod
     if (expr->op == ast::BinaryOp::kModulo && lhs_type->is_float_scalar_or_vector()) {
         out << "fmod";
-        ScopedParen sp(out.stream());
+        ScopedParen sp(out);
         if (!EmitExpression(out, expr->lhs)) {
             return false;
         }
@@ -549,7 +549,7 @@ bool GeneratorImpl::EmitBinary(utils::StringStream& out, const ast::BinaryExpres
         // WGSL defines behaviour for signed overflow, MSL does not. For these
         // cases, bitcast operands to unsigned, then cast result to signed.
         ScopedBitCast outer_int_cast(this, out, target_type, signed_type_of(target_type));
-        ScopedParen sp(out.stream());
+        ScopedParen sp(out);
         {
             ScopedBitCast lhs_uint_cast(this, out, lhs_type, unsigned_type_of(target_type));
             if (!EmitExpression(out, expr->lhs)) {
@@ -576,7 +576,7 @@ bool GeneratorImpl::EmitBinary(utils::StringStream& out, const ast::BinaryExpres
         // Shift left: discards top bits, so convert first operand to unsigned
         // first, then convert result back to signed
         ScopedBitCast outer_int_cast(this, out, lhs_type, signed_type_of(lhs_type));
-        ScopedParen sp(out.stream());
+        ScopedParen sp(out);
         {
             ScopedBitCast lhs_uint_cast(this, out, lhs_type, unsigned_type_of(lhs_type));
             if (!EmitExpression(out, expr->lhs)) {
@@ -595,7 +595,7 @@ bool GeneratorImpl::EmitBinary(utils::StringStream& out, const ast::BinaryExpres
     // Handle '&' and '|' of booleans.
     if ((expr->IsAnd() || expr->IsOr()) && lhs_type->Is<type::Bool>()) {
         out << "bool";
-        ScopedParen sp(out.stream());
+        ScopedParen sp(out);
         if (!EmitExpression(out, expr->lhs)) {
             return false;
         }
@@ -609,7 +609,7 @@ bool GeneratorImpl::EmitBinary(utils::StringStream& out, const ast::BinaryExpres
     }
 
     // Emit as usual
-    ScopedParen sp(out.stream());
+    ScopedParen sp(out);
     if (!EmitExpression(out, expr->lhs)) {
         return false;
     }
@@ -748,7 +748,7 @@ bool GeneratorImpl::EmitBuiltinCall(utils::StringStream& out,
             if (sem->Type()->UnwrapRef()->is_scalar()) {
                 // Emulate scalar overload using fabs(x - y);
                 out << "fabs";
-                ScopedParen sp(out.stream());
+                ScopedParen sp(out);
                 if (!EmitExpression(out, expr->args[0])) {
                     return false;
                 }
@@ -866,7 +866,7 @@ bool GeneratorImpl::EmitAtomicCall(utils::StringStream& out,
     auto call = [&](const std::string& name, bool append_memory_order_relaxed) {
         out << name;
         {
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
             for (size_t i = 0; i < expr->args.Length(); i++) {
                 auto* arg = expr->args[i];
                 if (i > 0) {
@@ -1646,7 +1646,7 @@ bool GeneratorImpl::EmitZeroValue(utils::StringStream& out, const type::Type* ty
             if (!EmitType(out, mat, "")) {
                 return false;
             }
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
             return EmitZeroValue(out, mat->type());
         },
         [&](const type::Array*) {
@@ -1693,7 +1693,7 @@ bool GeneratorImpl::EmitConstant(utils::StringStream& out, const constant::Value
                 return false;
             }
 
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
 
             if (constant->AllEqual()) {
                 if (!EmitConstant(out, constant->Index(0))) {
@@ -1717,7 +1717,7 @@ bool GeneratorImpl::EmitConstant(utils::StringStream& out, const constant::Value
                 return false;
             }
 
-            ScopedParen sp(out.stream());
+            ScopedParen sp(out);
 
             for (size_t i = 0; i < m->columns(); i++) {
                 if (i > 0) {
@@ -3286,7 +3286,7 @@ bool GeneratorImpl::CallBuiltinHelper(utils::StringStream& out,
     // Call the helper
     out << fn;
     {
-        ScopedParen sp(out.stream());
+        ScopedParen sp(out);
         bool first = true;
         for (auto* arg : call->args) {
             if (!first) {
diff --git a/src/tint/writer/text_generator.cc b/src/tint/writer/text_generator.cc
index 7534835ec8..20c5fe764f 100644
--- a/src/tint/writer/text_generator.cc
+++ b/src/tint/writer/text_generator.cc
@@ -114,7 +114,7 @@ void TextGenerator::TextBuffer::Insert(const TextBuffer& tb, size_t before, uint
 }
 
 std::string TextGenerator::TextBuffer::String(uint32_t indent /* = 0 */) const {
-    std::stringstream ss;
+    utils::StringStream ss;
     for (auto& line : lines) {
         if (!line.content.empty()) {
             for (uint32_t i = 0; i < indent + line.indent; i++) {
@@ -127,7 +127,7 @@ std::string TextGenerator::TextBuffer::String(uint32_t indent /* = 0 */) const {
     return ss.str();
 }
 
-TextGenerator::ScopedParen::ScopedParen(std::ostream& stream) : s(stream) {
+TextGenerator::ScopedParen::ScopedParen(utils::StringStream& stream) : s(stream) {
     s << "(";
 }
 
diff --git a/src/tint/writer/text_generator.h b/src/tint/writer/text_generator.h
index b53aef0f7c..74e3ecbf64 100644
--- a/src/tint/writer/text_generator.h
+++ b/src/tint/writer/text_generator.h
@@ -140,9 +140,6 @@ class TextGenerator {
         /// Destructor
         ~LineWriter();
 
-        /// [DEPRECATED] Remove when utils::StringStream conversion is done
-        /// @returns the utils::StringStream
-        operator std::ostream&() { return os.stream(); }
         /// @returns the utils::StringStream
         operator utils::StringStream&() { return os; }
 
@@ -164,9 +161,8 @@ class TextGenerator {
     /// Helper for writing a '(' on construction and a ')' destruction.
     struct ScopedParen {
         /// Constructor
-        /// [DEPRECATED] This should be utils::StringStream when conversion is done
-        /// @param stream the std::ostream that will be written to
-        explicit ScopedParen(std::ostream& stream);
+        /// @param stream the utils::StringStream that will be written to
+        explicit ScopedParen(utils::StringStream& stream);
         /// Destructor
         ~ScopedParen();
 
@@ -174,7 +170,7 @@ class TextGenerator {
         ScopedParen(ScopedParen&& rhs) = delete;
         ScopedParen(const ScopedParen&) = delete;
         ScopedParen& operator=(const ScopedParen&) = delete;
-        std::ostream& s;
+        utils::StringStream& s;
     };
 
     /// Helper for incrementing indentation on construction and decrementing