Received response to my bug report, asking me to test with Xcode 26.5. Cannot reproduce any longer the warnings so closed the bug report

They updated my bug report so it says: Recent Similar Reports:None Resolution:Open So please just wait they acknowledged it

This does not affect old projects only, create a new macOS app with the default settings and it'll suffer from the same problem unless you delete every menu item from the storyboard. reported FB21137001