I keep wondering how long it will take for putting borders and edges or some graphical hint around functional UI elements (whether 3d or not) to come back into

I keep wondering how long it will take for putting borders and edges or some graphical hint around functional UI elements (whether 3d or not) to come back into style. It's such a clear example of form over function to remove these (and if you ask me it doesn't even look good anyway, but let's put aesthetics aside). I would love to hear from any actual UX professional who wants to try to defend that making functional elements look identical to non-functional ones is a good idea. I would be fascinated to hear what the argument in its favor could possibly be.