diff --git a/packages/plugin_platform_interface/CHANGELOG.md b/packages/plugin_platform_interface/CHANGELOG.md
index d63cc2a..b45ca28 100644
--- a/packages/plugin_platform_interface/CHANGELOG.md
+++ b/packages/plugin_platform_interface/CHANGELOG.md
@@ -1,5 +1,6 @@
-## NEXT
+## 2.1.5
 
+* Updates README to improve example and discuss `base`.
 * Updates minimum Flutter version to 3.3.
 
 ## 2.1.4
diff --git a/packages/plugin_platform_interface/README.md b/packages/plugin_platform_interface/README.md
index 1b1f804..c53b98d 100644
--- a/packages/plugin_platform_interface/README.md
+++ b/packages/plugin_platform_interface/README.md
@@ -2,8 +2,8 @@
 
 This package provides a base class for platform interfaces of [federated flutter plugins](https://flutter.dev/go/federated-plugins).
 
-Platform implementations should extend their platform interface classes rather than implement it as
-newly added methods to platform interfaces are not considered as breaking changes. Extending a platform
+Platform implementations should `extends` their platform interface class rather than `implement`s it, as
+newly added methods to platform interfaces are not considered breaking changes. Extending a platform
 interface ensures that subclasses will get the default implementations from the base class, while
 platform implementations that `implements` their platform interface will be broken by newly added methods.
 
@@ -12,24 +12,34 @@
 
 ## Sample usage:
 
+<?code-excerpt "test/plugin_platform_interface_test.dart (Example)"?>
 ```dart
-abstract class UrlLauncherPlatform extends PlatformInterface {
-  UrlLauncherPlatform() : super(token: _token);
-
-  static UrlLauncherPlatform _instance = MethodChannelUrlLauncher();
+abstract class SamplePluginPlatform extends PlatformInterface {
+  SamplePluginPlatform() : super(token: _token);
 
   static final Object _token = Object();
 
-  static UrlLauncherPlatform get instance => _instance;
+  // A plugin can have a default implementation, as shown here, or `instance`
+  // can be nullable, and the default instance can be null.
+  static SamplePluginPlatform _instance = SamplePluginDefault();
 
-  /// Platform-specific plugins should set this with their own platform-specific
-  /// class that extends [UrlLauncherPlatform] when they register themselves.
-  static set instance(UrlLauncherPlatform instance) {
+  static SamplePluginPlatform get instance => _instance;
+
+  /// Platform-specific implementations should set this to their own
+  /// platform-specific class that extends [SamplePluginPlatform] when they
+  /// register themselves.
+  static set instance(SamplePluginPlatform instance) {
     PlatformInterface.verify(instance, _token);
     _instance = instance;
   }
 
- }
+  // Methods for the plugin's platform interface would go here, often with
+  // implementations that throw UnimplementedError.
+}
+
+class SamplePluginDefault extends SamplePluginPlatform {
+  // A default real implementation of the platform interface would go here.
+}
 ```
 
 This guarantees that UrlLauncherPlatform.instance cannot be set to an object that `implements`
@@ -45,8 +55,24 @@
 
 For example, a Mockito mock of a platform interface can be created with:
 
+<?code-excerpt "test/plugin_platform_interface_test.dart (Mock)"?>
 ```dart
-class UrlLauncherPlatformMock extends Mock
-   with MockPlatformInterfaceMixin
-   implements UrlLauncherPlatform {}
+class SamplePluginPlatformMock extends Mock
+    with MockPlatformInterfaceMixin
+    implements SamplePluginPlatform {}
 ```
+
+## A note about `base`
+
+In Dart 3, [the `base` keyword](https://dart.dev/language/class-modifiers#base)
+was introduced to the language, which enforces that subclasses use `extends`
+rather than `implements` at compile time. The Flutter team is
+[considering deprecating this package in favor of using
+`base`](https://github.com/flutter/flutter/issues/127396) for platfom interfaces,
+but no decision has been made yet since it removes the ability to do mocking/faking
+as shown above.
+
+Plugin authors may want to consider using `base` instead of this package when
+creating new plugins.
+
+https://github.com/flutter/flutter/issues/127396
diff --git a/packages/plugin_platform_interface/pubspec.yaml b/packages/plugin_platform_interface/pubspec.yaml
index 9ccd4a0..2bd3909 100644
--- a/packages/plugin_platform_interface/pubspec.yaml
+++ b/packages/plugin_platform_interface/pubspec.yaml
@@ -15,7 +15,7 @@
 # be done when absolutely necessary and after the ecosystem has already migrated to 2.X.Y version
 # that is forward compatible with 3.0.0 (ideally the ecosystem have migrated to depend on:
 # `plugin_platform_interface: >=2.X.Y <4.0.0`).
-version: 2.1.4
+version: 2.1.5
 
 environment:
   sdk: ">=2.18.0 <4.0.0"
diff --git a/packages/plugin_platform_interface/test/plugin_platform_interface_test.dart b/packages/plugin_platform_interface/test/plugin_platform_interface_test.dart
index 869017c..00da4a1 100644
--- a/packages/plugin_platform_interface/test/plugin_platform_interface_test.dart
+++ b/packages/plugin_platform_interface/test/plugin_platform_interface_test.dart
@@ -6,18 +6,35 @@
 import 'package:plugin_platform_interface/plugin_platform_interface.dart';
 import 'package:test/test.dart';
 
-class SamplePluginPlatform extends PlatformInterface {
+// #docregion Example
+abstract class SamplePluginPlatform extends PlatformInterface {
   SamplePluginPlatform() : super(token: _token);
 
   static final Object _token = Object();
 
-  // ignore: avoid_setters_without_getters
+  // A plugin can have a default implementation, as shown here, or `instance`
+  // can be nullable, and the default instance can be null.
+  static SamplePluginPlatform _instance = SamplePluginDefault();
+
+  static SamplePluginPlatform get instance => _instance;
+
+  /// Platform-specific implementations should set this to their own
+  /// platform-specific class that extends [SamplePluginPlatform] when they
+  /// register themselves.
   static set instance(SamplePluginPlatform instance) {
     PlatformInterface.verify(instance, _token);
-    // A real implementation would set a static instance field here.
+    _instance = instance;
   }
+
+  // Methods for the plugin's platform interface would go here, often with
+  // implementations that throw UnimplementedError.
 }
 
+class SamplePluginDefault extends SamplePluginPlatform {
+  // A default real implementation of the platform interface would go here.
+}
+// #enddocregion Example
+
 class ImplementsSamplePluginPlatform extends Mock
     implements SamplePluginPlatform {}
 
@@ -27,11 +44,13 @@
   dynamic noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
 }
 
-class ImplementsSamplePluginPlatformUsingMockPlatformInterfaceMixin extends Mock
+// #docregion Mock
+class SamplePluginPlatformMock extends Mock
     with MockPlatformInterfaceMixin
     implements SamplePluginPlatform {}
+// #enddocregion Mock
 
-class ImplementsSamplePluginPlatformUsingFakePlatformInterfaceMixin extends Fake
+class SamplePluginPlatformFake extends Fake
     with MockPlatformInterfaceMixin
     implements SamplePluginPlatform {}
 
@@ -112,14 +131,12 @@
     });
 
     test('allows mocking with `implements`', () {
-      final SamplePluginPlatform mock =
-          ImplementsSamplePluginPlatformUsingMockPlatformInterfaceMixin();
+      final SamplePluginPlatform mock = SamplePluginPlatformMock();
       SamplePluginPlatform.instance = mock;
     });
 
     test('allows faking with `implements`', () {
-      final SamplePluginPlatform fake =
-          ImplementsSamplePluginPlatformUsingFakePlatformInterfaceMixin();
+      final SamplePluginPlatform fake = SamplePluginPlatformFake();
       SamplePluginPlatform.instance = fake;
     });
 
diff --git a/script/configs/temp_exclude_excerpt.yaml b/script/configs/temp_exclude_excerpt.yaml
index 7736efb..4d712ed 100644
--- a/script/configs/temp_exclude_excerpt.yaml
+++ b/script/configs/temp_exclude_excerpt.yaml
@@ -22,8 +22,6 @@
 - ios_platform_images
 - multicast_dns
 - palette_generator
-- pigeon
-- plugin_platform_interface
 - pointer_interceptor
 - quick_actions/quick_actions
 - webview_flutter_android