Tying that choice to the choice of hardware and operating system is anti-competitive.
Except you've just invented that arbitrary distinction.
You can't seriously suggest that a Microwave, Treadmill, Car, Calculator, Thermometer etc would all need to invest the ridiculous amounts of time/money in supporting users wishing to install alternate operating systems.
It just blows my mind a little when I imagine the walled garden approach being applied more broadly and earlier. E.g. if the creators of web browsers and search engines had all decided they want a cut of sales from websites. (I mean a cut of sales from organic search, not just ads. And all sales made using the browser.)
Those “what might have been” scenarios tend to make me less comfortable with my iPad and my Android phone. But I still have them because I like them.