I can see both sides of the argument here. It sucks having no choice as a developer, and feeling forced pay Apple a tax just to get paid for your work. It's especially egregious with subscriptions, where Apple doesn't even do any of the content delivery. However, as a user, I think it would also suck if a huge player like Facebook or Google decided to open up their own iOS App Stores, and developers started flocking to them as a means to escape Apples increasingly strict app privacy rules.