I tend to use my credit card for most of my purchases, online or in-person. In doing so, I haven’t come across the problem of payments you describe, although I’m unaware if the apps I use utilise Google’s API in the back-end to do this (for example, does the Amazon app use some Android API to process my payment using a credit card?).
I think I’d be fine without most Google apps except for Maps, where OpenStreetMap has not served me well so fat (unfortunate, since I would like to use it but it is not as reliable in my experience). I can do my banking in the browser, and consume my video content (YouTube/Peertube/LBRY) in the browser anyway.
I’m going to revisit the Murena mobiles again, and I’ll reiterate how disappointed I am that the FP5 is not available in the US. At this point, I’ll pin my hopes on KernelSU for the next few years (hoping I don’t have to compile my own kernel, I’d like to get a cheap device running the 5.10 kernel or those after it), but consumer devices don’t have hardware killswitches or privacy features or replaceable parts either (and iFixit doesn’t cover every device).
This was a long comment, and I appreciate this discourse with you. Thanks again.