you can't really copyright UI beyond the design itself, the functionality is free game as far as I understand.
It's not just copyright. There are also patents to worry about. Those cover a specific process, like "click here, and the code selects all regions matching the same color (+-5%)". If you make an exact copy, surely you've violated some patents.
Sure, patent protections don't last as long as copyright, and they can be defeated if you prove that it's "obvious" or can show prior art, but it's still an expensive legal battle against a megacorp. A vibe coder will likely fold at the first cease and desist.