Are they really deleting menu bars? Wow. Maybe in ten years time they'll figure out that two hamburgers is better than one; and that they'll need names like "File" and "Edit".
https://docs.gtk.org/gtk4/migrating-3to4.html#gtkmenu-gtkmen...
I wish the GP would clarify this particular confusion in their comment! The way it stands, the comment makes these projects sound outright whimsical, which is clearly not true.