But Android in general doesn’t have these restrictions. Plenty of phones (including Google’s flagships!) support rooting, and you can install a third-party App

But Android in general doesn’t have these restrictions. Plenty of phones (including Google’s flagships!) support rooting, and you can install a third-party App Store like F-droid even when they only support sideloading. So that’s not really a good example of market forces failing to solve the unlocked hardware availability problem.