> I simply will not buy a car that won't easily accept a double DIN head unit.

Are those even a thing anymore? The vast majority of new cars have some sort of custom all-in-one dashboard display.

I don't know or care if "it's a thing anymore", there's an inexhaustible supply of existing cars with double DIN. My Subaru from 2017 has double DIN and I don't see any reason to own a more modern car than that.