Yes but the 30% cut (which is supposedly taking advantage of their monopoly) existed from the very beginning. They didn't eventually become a monopoly and then up prices to extort money from developers. From the very start they charged 30%, and despite of that fee, they still gained a huge market share. I would argue that because they were able to gain a monopoly without changing their fees, that the fees are not taking advantage of monopoly whatsoever.
It is not a monopoly. You are spinned. The answer is key. Can’t be monopoly like this legally. Otherwise you may be charged of monopoly of selling coffee in your backyard as only you can do it.
Not just that, to be honest Apple App do not spill over even. You do not need to run in Apple store unlike in 1990 you basically have to run windows.