Fix more cases of hardcoded assembly names.

src/ObjCRuntime/Registrar.cs

@@ -1284,30 +1284,50 @@ internal string AssemblyName
 			get {
 				switch (App.Platform) {
 				case ApplePlatform.iOS:
-					return "Xamarin.iOS";
+					return Driver.IsDotNet ? "Microsoft.iOS" : "Xamarin.iOS";
 				case ApplePlatform.WatchOS:
-					return "Xamarin.WatchOS";
+					return Driver.IsDotNet ? "Microsoft.watchOS" : "Xamarin.WatchOS";
 				case ApplePlatform.TVOS:
-					return "Xamarin.TVOS";
+					return Driver.IsDotNet ? "Microsoft.tvOS" : "Xamarin.TVOS";
 				case ApplePlatform.MacOSX:
-					return "Xamarin.Mac";
+					return Driver.IsDotNet ? "Microsoft.macOS" : "Xamarin.Mac";
 				case ApplePlatform.MacCatalyst:
-					return "Xamarin.MacCatalyst";
+					return Driver.IsDotNet ? "Microsoft.MacCatalyst" : "Xamarin.MacCatalyst";
 				default:
 					throw ErrorHelper.CreateError (71, Errors.MX0071, App.Platform, App.ProductName);
 				}
 			}
 		}
 #elif MONOMAC
+#if NET
+		internal const string AssemblyName = "Microsoft.macOS";
+#else
 		internal const string AssemblyName = "Xamarin.Mac";
+#endif
 #elif WATCH
+#if NET
+		internal const string AssemblyName = "Microsoft.watchOS";
+#else
 		internal const string AssemblyName = "Xamarin.WatchOS";
+#endif
 #elif TVOS
+#if NET
+		internal const string AssemblyName = "Microsoft.tvOS";
+#else
 		internal const string AssemblyName = "Xamarin.TVOS";
+#endif
 #elif __MACCATALYST__
+#if NET
+		internal const string AssemblyName = "Microsoft.MacCatalyst";
+#else
 		internal const string AssemblyName = "Xamarin.MacCatalyst";
+#endif
 #elif IOS
+#if NET
+		internal const string AssemblyName = "Microsoft.iOS";
+#else
 		internal const string AssemblyName = "Xamarin.iOS";
+#endif
 #else
 #error Unknown platform
 #endif