diff --git a/src/libraries/System.Text.Json/gen/JsonSourceGenerator.Emitter.cs b/src/libraries/System.Text.Json/gen/JsonSourceGenerator.Emitter.cs
index cefc1c51e2f5ca..80b648dfd95803 100644
--- a/src/libraries/System.Text.Json/gen/JsonSourceGenerator.Emitter.cs
+++ b/src/libraries/System.Text.Json/gen/JsonSourceGenerator.Emitter.cs
@@ -137,27 +137,16 @@ private static SourceWriter CreateSourceWriterWithContextHeader(ContextGeneratio
             {
                 var writer = new SourceWriter();
 
-                // In release builds of the generator, we suppress all diagnostics stemming from the generated code.
-                // There's nothing a developer can do about these diagnostics, and they can break the build. In debug
-                // builds, we allow more warnings in order to catch potential issues early.
-#if DEBUG
                 writer.WriteLine("""
                     // <auto-generated/>
 
                     #nullable enable annotations
                     #nullable disable warnings
-                    #pragma warning disable CS0612, CS0618 // [Obsolete] member usage
 
-                    """);
-#else
-                writer.WriteLine("""
-                    // <auto-generated/>
-
-                    #nullable enable annotations
-                    #pragma warning disable
+                    // Suppress warnings about [Obsolete] member usage in generated code.
+                    #pragma warning disable CS0612, CS0618
 
                     """);
-#endif
 
                 if (contextSpec.Namespace != null)
                 {
diff --git a/src/libraries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Unit.Tests/CompilationHelper.cs b/src/libraries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Unit.Tests/CompilationHelper.cs
index 12175d068e0f4b..37f6c74e172c0d 100644
--- a/src/libraries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Unit.Tests/CompilationHelper.cs
+++ b/src/libraries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Unit.Tests/CompilationHelper.cs
@@ -184,16 +184,6 @@ internal sealed class CompilerFeatureRequiredAttribute : Attribute
                     public CompilerFeatureRequiredAttribute(string featureName) { }
                 }
             }
-
-            namespace System.Diagnostics.CodeAnalysis
-            {
-                internal sealed class ExperimentalAttribute : Attribute
-                {
-                    public ExperimentalAttribute(string diagnosticId) => DiagnosticId = diagnosticId;
-                    public string DiagnosticId { get; }
-                    public string UrlFormat { get; set; }
-                }
-            }
             """;
 #endif
 
diff --git a/src/libraries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Unit.Tests/JsonSourceGeneratorTests.cs b/src/libraries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Unit.Tests/JsonSourceGeneratorTests.cs
index 858b7176a3d176..185881ccbcd16c 100644
--- a/src/libraries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Unit.Tests/JsonSourceGeneratorTests.cs
+++ b/src/libraries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Unit.Tests/JsonSourceGeneratorTests.cs
@@ -521,36 +521,6 @@ public class ClassWithObsolete
             CompilationHelper.RunJsonSourceGenerator(compilation);
         }
 
-        [Fact]
-        public static void NoWarningsDueToExperimentalMembers()
-        {
-            string source = """
-                using System;
-                using System.Diagnostics.CodeAnalysis;
-                using System.Text.Json.Serialization;
-
-                namespace Test
-                {
-                #pragma warning disable TEST001
-                    [JsonSerializable(typeof(ClassWithExperimental))]
-                #pragma warning restore TEST001
-                    public partial class JsonContext : JsonSerializerContext { }
-
-                    public class ClassWithExperimental
-                    {
-                        [Experimental("TEST001")]
-                        public bool Test { get; set; }
-
-                        [Experimental("TEST002")]
-                        public bool Test2 { get; set; }
-                    }
-                }
-                """;
-
-            Compilation compilation = CompilationHelper.CreateCompilation(source);
-            CompilationHelper.RunJsonSourceGenerator(compilation);
-        }
-
         [Fact]
         public static void NoErrorsWhenUsingReservedCSharpKeywords()
         {