If anyone cared to look up the definition of "monopoly" they'd see right there that the App Store is one. And by the way- monopolies are illegal
1) Monopolies aren’t illegal per se.
2) It’s not illegal to be a monopoly.
3) It’s not illegal to have a monopoly on your own products - it’s expected. Of course Apple has a monopoly on iOS, of course they have a monopoly on the iOS App Store - it’s THEIR product. Just like MacDonalds have a monopoly on Big Macs.
4) It’s not illegal to become a monopoly through better products, services or business acumen.
5) It’s not illegal to become a monopoly through happenstance.
The only time it is illegal to be a monopoly is if you abused your position to attain or maintain a monopoly.