I remember that there was an identifier based on model number. FaceTime wasn’t allowed in the Middle East for a while, there was a way to tell if the model will support it based on the last character after the / in the model number. Middle East models won’t even have the app at all.

Propably they’ll do the same for models sold in the EU.

There are already hardware variants of the same iPhone. I think the US gets an iPhone with all eSIM, and China has two physical SIM slots.