$2.8 billion/year in developer fees, or about 0.75% of total annual revenue.$99/year per developer for how many developers, plus ApplePay and IAP, me thinks that is not pocket change.
$4 billion ApplePay revenue (not profit).
$64 billion from the app store.
In comparison, AWS made $40 billion revenue last year.
And I'll state it again: ApplePay is only one choice among many you can use for Apple goods and services. They are not forcing anybody to use any particular payment method.