Sooner or later I'll find the time.
Personally I think I could do it. I use Google for calendar sync, but there are other providers. I sometimes use Google Maps, but I have other apps that substitute for that just fine (in fact I probably use Google less than Open Streetmap-based apps). And those are the two Google services I use most, and I reckon I can dispense with both (the calendar sync will be the harder, but there are other CalDav servers out there and I don't actually share calendars with people). I can't think of any other Google service I can't do without: F-Droid and APKMirror cover app requirements, I don't use Assistant, don't get media from Google, don't need Photos, and anyway most Google services can be accessed with a browser if you really need them. So my guess is that I could walk away from Google completely if I wanted, and a phone with no Google certainly seems doable to me.