Regarding your edit: Apple has already shown some power here in negotiation between the big card networks. Apple Card has been on MasterCard since it began, but

Regarding your edit: Apple has already shown some power here in negotiation between the big card networks. Apple Card has been on MasterCard since it began, but Apple Cash has "quietly" switched networks presumably as Apple has negotiated lower rates. Apple Cash being a "debit card" is even more affected by the network overheads than credit cards. (Cash was on Discover's Debit network for a bunch of years but is currently on Visa's Debit network. I don't think it has yet been on MasterCard's, despite the Apple Card being home on MasterCard.) I don't know if Apple alone can fix some of our card transaction overhead, but it is interesting to note that they don't appear to be a passive player either.