Look into GrapheneOS. It’s pretty easy to install on a Pixel device if you’re willing to spend a few hours on it (might be less, assuming all your USB cables work first go 'round, unlike mine 🙄) and it’s been a great daily driver for me. You don’t have to install Google Play stuff, but if you need it for an app like banking you can run it all sandboxed and control all the permissions. Only thing I lost was Gboard’s ability to send GIFs (because I have it sandboxed; I could get it back if I wanted to let it connect to the internet). You might be able to get a Pixel 6a for like $200 soon too, I think I saw something about a sale coming up on the Google store.