[aaomidi]

An alternative would be to open up the payment provider api to different processors.

For example if my bank implements the payment provider API, then let me use that. All the other apps need to care about is a payment request method which can be satisfied with whatever payment provider I have picked.

Apps would be able to ask the provider how much they’re gonna get after the payment processes etc, and decide if they want to reject it or not.

[_scr00bius_]

That's not how corporate commercial agreements work.. apple would better immediately bogged down in multiple, endless negotiations and trial periods. As a developer, I don't think you should want apple involved in your processor choice at all

[aaomidi]

Apple acts as the API provider, they don't need to "bless" anything here.