Since iOS's inception, it has run the exact same kernel as the Mac. They developed separate UI layers for separate devices, but the underlying system has always

Since iOS's inception, it has run the exact same kernel as the Mac. They developed separate UI layers for separate devices, but the underlying system has always been the same. They do seem to be bringing the higher level components together where they can, which seems smart from a maintainability perspective. macOS becoming a walled garden? Maybe, but it has nothing to do with them sticking a Touch Bar running a variant of watchOS on their laptop.