I think no can disagree that this is at least a step in the right direction
I do this on my OnePlus, I install apps through F-Droid and Aurora store to try to preserve some shred of privacy while not being too feature limited. In particular google push messages still work. I also kick unwanted system apps off with ADB. It's a compromise compared to a really clean ROM but it's possible.
It's not possible to use a Quest without an account.
What about a Pixel phone?
But on those there are some particularly excellent custom ROM offerings, like CalyxOS and GrapheneOS.
I was thinking of buying a pixel 4a just for that purpose yesterday with the google day discount but in the end I cancelled it :) As I already have a decent phone.