diff --git a/Library/Homebrew/diagnostic.rb b/Library/Homebrew/diagnostic.rb
index f8508cea3e..73d206b9fe 100644
--- a/Library/Homebrew/diagnostic.rb
+++ b/Library/Homebrew/diagnostic.rb
@@ -908,6 +908,19 @@ module Homebrew
         EOS
       end
 
+      def check_deprecated_cask_taps
+        tapped_caskroom_taps = ::Tap.select { |t| t.user == "caskroom" || t.name == "phinze/cask" }
+                                    .map(&:name)
+        return if tapped_caskroom_taps.empty?
+
+        <<~EOS
+          You have the following deprecated Cask taps installed:
+            #{tapped_caskroom_taps.join("\n  ")}
+          Please remove them with:
+            brew untap #{tapped_caskroom_taps.join(" ")}
+        EOS
+      end
+
       def check_cask_software_versions
         add_info "Homebrew Version", HOMEBREW_VERSION
 
diff --git a/Library/Homebrew/extend/os/mac/diagnostic.rb b/Library/Homebrew/extend/os/mac/diagnostic.rb
index 5b663e233b..8c60b8ba30 100644
--- a/Library/Homebrew/extend/os/mac/diagnostic.rb
+++ b/Library/Homebrew/extend/os/mac/diagnostic.rb
@@ -424,18 +424,6 @@ module OS
           EOS
         end
 
-        def check_deprecated_caskroom_taps
-          tapped_caskroom_taps = ::Tap.select { |t| t.user == "caskroom" || t.name == "phinze/cask" }
-                                      .map(&:name)
-          return if tapped_caskroom_taps.empty?
-
-          <<~EOS
-            You have the following deprecated, cask taps tapped:
-              #{tapped_caskroom_taps.join("\n  ")}
-            Untap them with `brew untap`.
-          EOS
-        end
-
         def check_if_supported_sdk_available
           return unless ::DevelopmentTools.installed?
           return unless MacOS.sdk_root_needed?