Wallet Apps and Tap-to-pay do not work. Even got banned from PayPal. Android needs an architectural change from the ground up.
I mean you're not degoogling yourself if you put all your transactions through a google server. Cash if possible, card if not.
(Also it is possible to do these things if you root your phone, but caries its own risks and I wouldn't recommend. Ending your dependency on third party processors is probably the best outcome)
If you don't use the paypal app, you should be fine, right?
I'm happy with grapheneOS as a daily driver. Can you elaborate on being banned from paypal so I don't do the same ?