That old model just wasn’t sustainable. Developers needed to constantly sell copies to new customers just to keep the lights on. It worked for small-time, one-off apps like a pdf reader but for games, particularly with multiplayer or online features they have to pay employees salaries and server costs too.

At some point the customer base was maxed out and sales slowed.

I went back in my app list to the beginning when the App Store launched and so many of the companies that made those early apps are just gone now. Blaming Apple as being greedy is reductive and overly simplistic.