I believe that's how Google is doing it, but Apple is not

Google does a 15% progressive fee for the first $1mil. Apple sorta does the same, though once you cross the $1mil threshold, you pay a 30% cut next year on all your sales.

This article [0] says the Play Store takes 15% from the first million but Apple's store takes 30% of everything once you pass one million/year. But it also makes it clear that only a very small percentage of apps in either store make more than one million/year.

Another article [1] says 98% of developers in the Apple store would be below one million/year but also that that long tail generates only 5% of the store's revenue. There are a tiny number of apps that are enormous winners, games I assume, and there's everything else.

[0] https://techcrunch.com/2021/03/18/data-shows-how-few-google-...

[1] https://www.theverge.com/2020/11/18/21572302/apple-app-store...