And when the EU forces them to do so, Apple will limit it to just those in the EU, all the while complaining it limits Apple’s ability to “innovate,” which hasn’t been been fully explained as to how having multiple app stores, etc., impairs said ability.
I mean, it has been fully explained. You (that is, people who take your position) just don't agree with it.
When Apple says "it limits our ability to innovate" with respect to multiple app stores and various software features, what they're saying is, "it limits our ability to add new features while ensuring those features provide a consistent experience across all apps on our platforms".
You see the restrictions on something like Apple Pay and say, "Oh, Apple wants to monopolize payments on its devices to suppress competition." Apple looks at it and says, "By controlling the payment experience, when we add something new, it's available
everywhere, in all apps, where on-device payments can be made, and it works and functions
exactly the same way in all of those places."
You see something like the App Store and say, "Oh, Apple wants to monopolize apps so it can enforce its authoritarian policies and keep its revenue stream". Apple looks at it and says, "By controlling the app sourcing experience, we can provide a consistent, always-present source for applications, ensure some degree of consistency in behavior and look-and-feel, and through app review, try and weed out as much garbage as we reasonably can."
Is Apple a pure-hearted angel? Of course not. I'm sure the competitive effects and the revenue streams of these decisions aren't lost on them. It's a corporation, after all. Few decisions are going to be solely about the competition or the money, though, and
of course you're not going to see the "full explanation" you claim to be looking for when your world view doesn't align with theirs.