>Pretty much all Apple has to do to keep apps in App Store in the face of competition is drop their fees to less than 10% for all apps and drop bullshit like "you can't even link to your website if it lets users pay from there", and almost everyone except the most brazen will stay on App Store.

Exactly. Apple would have to actually... compete. I suppose I can understand why this fills them with dread, but they have a clear path to retaining developers: compete!