diff --git a/src/main/java/com/google/devtools/build/lib/packages/StarlarkSemanticsOptions.java b/src/main/java/com/google/devtools/build/lib/packages/StarlarkSemanticsOptions.java
index 890c9c1ed3f891..97f5ace13fb75e 100644
--- a/src/main/java/com/google/devtools/build/lib/packages/StarlarkSemanticsOptions.java
+++ b/src/main/java/com/google/devtools/build/lib/packages/StarlarkSemanticsOptions.java
@@ -343,18 +343,6 @@ public class StarlarkSemanticsOptions extends OptionsBase implements Serializabl
       help = "If set to true, the default value of the `allow_empty` argument of glob() is False.")
   public boolean incompatibleDisallowEmptyGlob;
 
-  @Option(
-      name = "incompatible_disallow_hashing_frozen_mutables",
-      defaultValue = "true",
-      documentationCategory = OptionDocumentationCategory.STARLARK_SEMANTICS,
-      effectTags = {OptionEffectTag.BUILD_FILE_SEMANTICS},
-      metadataTags = {
-        OptionMetadataTag.INCOMPATIBLE_CHANGE,
-        OptionMetadataTag.TRIGGERED_BY_ALL_INCOMPATIBLE_CHANGES
-      },
-      help = "If set to true, freezing a mutable object will not make it hashable.")
-  public boolean incompatibleDisallowHashingFrozenMutables;
-
   @Option(
       name = "incompatible_disallow_legacy_javainfo",
       defaultValue = "true",
@@ -741,7 +729,6 @@ public StarlarkSemantics toSkylarkSemantics() {
             .incompatibleRestrictStringEscapes(incompatibleRestrictStringEscapes)
             .incompatibleDisallowDictLookupUnhashableKeys(
                 incompatibleDisallowDictLookupUnhashableKeys)
-            .incompatibleDisallowHashingFrozenMutables(incompatibleDisallowHashingFrozenMutables)
             .build();
     return INTERNER.intern(semantics);
   }
diff --git a/src/main/java/com/google/devtools/build/lib/syntax/EvalUtils.java b/src/main/java/com/google/devtools/build/lib/syntax/EvalUtils.java
index 370ccd616f2eff..676d0bee5569b8 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/EvalUtils.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/EvalUtils.java
@@ -123,11 +123,7 @@ public int compare(Object o1, Object o2) {
    */
   public static void checkValidDictKey(Object o, StarlarkThread thread) throws EvalException {
     // TODO(bazel-team): check that all recursive elements are both Immutable AND Comparable.
-    if (thread != null && thread.getSemantics().incompatibleDisallowHashingFrozenMutables()) {
-      if (isHashable(o)) {
-        return;
-      }
-    } else if (isImmutable(o)) {
+    if (isHashable(o)) {
       return;
     }
     // Same error message as Python (that makes it a TypeError).
@@ -149,11 +145,11 @@ public static boolean isHashable(Object o) {
 
   /**
    * Is this object known or assumed to be recursively immutable by Skylark?
+   *
    * @param o an Object
    * @return true if the object is known to be an immutable value.
    */
-  // NB: This is used as the basis for accepting objects in SkylarkNestedSet-s,
-  // as well as for accepting objects as keys for Skylark dict-s.
+  // NB: This is used as the basis for accepting objects in SkylarkNestedSet-s.
   public static boolean isImmutable(Object o) {
     if (o instanceof SkylarkValue) {
       return ((SkylarkValue) o).isImmutable();
diff --git a/src/main/java/com/google/devtools/build/lib/syntax/StarlarkSemantics.java b/src/main/java/com/google/devtools/build/lib/syntax/StarlarkSemantics.java
index ef5e224c88707d..e6acacafaa7d3b 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/StarlarkSemantics.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/StarlarkSemantics.java
@@ -220,8 +220,6 @@ public boolean flagValue(FlagIdentifier flagIdentifier) {
 
   public abstract boolean experimentalAllowTagsPropagation();
 
-  public abstract boolean incompatibleDisallowHashingFrozenMutables();
-
   @Memoized
   @Override
   public abstract int hashCode();
@@ -300,7 +298,6 @@ public static Builder builderWithDefaults() {
           .incompatibleDepsetForLibrariesToLinkGetter(true)
           .incompatibleRestrictStringEscapes(false)
           .incompatibleDisallowDictLookupUnhashableKeys(false)
-          .incompatibleDisallowHashingFrozenMutables(true)
           .build();
 
   /** Builder for {@link StarlarkSemantics}. All fields are mandatory. */
@@ -399,8 +396,6 @@ public abstract Builder incompatibleDisallowRuleExecutionPlatformConstraintsAllo
 
     public abstract Builder incompatibleDisallowDictLookupUnhashableKeys(boolean value);
 
-    public abstract Builder incompatibleDisallowHashingFrozenMutables(boolean value);
-
     public abstract StarlarkSemantics build();
   }
 }
diff --git a/src/test/java/com/google/devtools/build/lib/packages/SkylarkSemanticsConsistencyTest.java b/src/test/java/com/google/devtools/build/lib/packages/SkylarkSemanticsConsistencyTest.java
index 98359fa0c7dfc2..8edf8905ba4e3a 100644
--- a/src/test/java/com/google/devtools/build/lib/packages/SkylarkSemanticsConsistencyTest.java
+++ b/src/test/java/com/google/devtools/build/lib/packages/SkylarkSemanticsConsistencyTest.java
@@ -165,7 +165,6 @@ private static StarlarkSemanticsOptions buildRandomOptions(Random rand) throws E
         "--incompatible_visibility_private_attributes_at_definition=" + rand.nextBoolean(),
         "--incompatible_restrict_string_escapes=" + rand.nextBoolean(),
         "--incompatible_disallow_dict_lookup_unhashable_keys=" + rand.nextBoolean(),
-        "--incompatible_disallow_hashing_frozen_mutables=" + rand.nextBoolean(),
         "--internal_skylark_flag_test_canary=" + rand.nextBoolean());
   }
 
@@ -221,7 +220,6 @@ private static StarlarkSemantics buildRandomSemantics(Random rand) {
         .incompatibleVisibilityPrivateAttributesAtDefinition(rand.nextBoolean())
         .incompatibleRestrictStringEscapes(rand.nextBoolean())
         .incompatibleDisallowDictLookupUnhashableKeys(rand.nextBoolean())
-        .incompatibleDisallowHashingFrozenMutables(rand.nextBoolean())
         .internalSkylarkFlagTestCanary(rand.nextBoolean())
         .build();
   }
diff --git a/src/test/java/com/google/devtools/build/lib/skylark/SkylarkIntegrationTest.java b/src/test/java/com/google/devtools/build/lib/skylark/SkylarkIntegrationTest.java
index 4e0dbaf87e62ba..a09fc86c6b44f4 100644
--- a/src/test/java/com/google/devtools/build/lib/skylark/SkylarkIntegrationTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skylark/SkylarkIntegrationTest.java
@@ -3239,20 +3239,8 @@ public void testIdentifierAssignmentFromOuterScopeForbidden() throws Exception {
     assertContainsEvent("local variable 'a' is referenced before assignment");
   }
 
-  @Test
-  public void testHashFrozenList() throws Exception {
-    setSkylarkSemanticsOptions("--incompatible_disallow_hashing_frozen_mutables=false");
-    scratch.file("test/extension.bzl", "y = []");
-
-    scratch.file(
-        "test/BUILD", "load('//test:extension.bzl', 'y')", "{y: 1}", "cc_library(name = 'r')");
-
-    getConfiguredTarget("//test:r");
-  }
-
   @Test
   public void testHashFrozenListForbidden() throws Exception {
-    setSkylarkSemanticsOptions("--incompatible_disallow_hashing_frozen_mutables=true");
     scratch.file("test/extension.bzl", "y = []");
 
     scratch.file(
@@ -3265,7 +3253,6 @@ public void testHashFrozenListForbidden() throws Exception {
 
   @Test
   public void testHashFrozenDeepMutableForbidden() throws Exception {
-    setSkylarkSemanticsOptions("--incompatible_disallow_hashing_frozen_mutables=true");
     scratch.file("test/extension.bzl", "y = {}");
 
     scratch.file(