The look and feel of an interface could be covered under a design patent, which would be a different question than copyright, and a much higher bar to enforce (particularly, protection is far from automatic).

You’re talking about enforcement which is a fair point of view, but I’m taking about likelihood of getting sued and having to settle in order to avoid the risk of losing a case in court. Which is the more common case for situations where one company alleges the other stole their IP.