Been using pixel phones for that reason, since... Pixel XL, and six pixel phones since then. Used several different AOSP based OS-es, most recently CalyxOS on Pixel 4a, and then GrapheneOS on Pixel 6a and now the 8 Pro.

Everything works, and you can choose how much of Google you invite back in. The best part is that the Google stuff doesn't get any special treatment. Which means that the Pixel Camera app and Google Photos isn't allowed access to Internet, because why should it?

The only thing that is still fundamentally flawed, are remote push notifications. And I don't mean that it's flawed for GeapheneOS, they work fine. It's flawed in the sense that information goes through Google or Apple. The privacy concerns there are significant. It's not end-to-end encrypted. You cannot avoid the problem either by disabling them on your phone. Each application, be that a Ring Camera, or backend messaging system, etc, that sends the stuff to Google through notification apis, will do so regardless of how much you sandbox or disable those services on the phone-receiving end. Conveniently, there is no effort by Apple or Google to make this core functionality any less tied to Apple or Google. The "asynchronous" nature makes it a problem that needs to be solved for each and every backend service system, for remote notifications. Some privacy conscious apps/services might let you limit what is sent to Google so you only get "New message from Hubbie" instead of also "Hubbie: remember to buy the paint for the baby-room! I'm so excited".

Anyways... Not sure why I went on such a long tangent. I was done pooping a while ago.

CalyxOS on a Pixel is as great as it currently gets. But stuff can get better.