Earlier quoted context omitted.
Yeah, in a monopoly situation I see where you're coming from, but Apple has very healthy competition from Android. It's not currently in Apple's interest to hobble 3rd party apps; quite the opposite.
If Apple is a abusing his position as OS provider by using in their apps APIs that are not available to other app developers, I'm not sure if the right answer is "go and develop for Android instead". What I think it may be different in Apple's case is that they don't usually build apps that compete with apps from other developers like Microsoft did.
They sometimes do, though, with Maps for example.
... and Maps is precisely one of the apps that use private APIs.