They mention deindexing from browse and search. I understand this to mean you can still visit and buy the products, and list the publisher's titles on their publisher's page.
That's far from "banning". And doesn't prevent the supporting creators and browsing their catalog - the use-case OP described.
At the bottom, I see Visa and Mastercard. Not big enough yet, did not get contacted yet, or did not implement it yet?