For a lot of Apple users, the relative predictability that comes from the exclusive licensing on the App Store is a value-add.

There are, obviously, exceptions, but Apple's agreements arm them with ample tools to address the exceptions when they're discovered, since they're basically the emperor of their fiefdom.

I don't follow the reasoning here. Why would you march behind another company if you are happy with the one that you get your services from?

I would understand if Apple had a dominant market share like Google with no real alternatives or if was close to become like Google. If that was the case, I would be very sceptical but obviously that's not the case.