I think the only viable solution is going to be to have 2 devices: one for government and financial services and one for everything else, where you still have some hope of privacy.

This is what I'm thinking. Android supports multi-user, right? So a cheap Android POS shared with the family that gets left at home most of the time.

I also think just not using a phone as much is a viable solution. People are addicted to their phones so it would feel like intercision at first. But freedom is worth it. Never sacrifice freedom for convenience. You actually don't need to look up stuff on Wikipedia at any time while you're outside. Just be outside. Be offline. It's fine. It's better even.

I'd be happy just going back to a dumbphone for the phone bit and having a portable GNU/Linux device for travelling. I still have a 15 year old Dell netbook but sadly the battery is shot and it's no good for the wonderful "modern" web. But something like that would be fine.