Thats a good question. PIX is directly tied to your bank account, so I imagine if your bank decides to ban your account, you won't be able to use PIX through that account/bank anymore. But, I suppose you could open another account in another bank, move your previous PIX keys to it or create new ones.

Not how it works.. One banks bans you and you are screwed for life. That's the value proposition of bitcoin

Oh, didn't know that. Can you point out where it says that? From what I understand of PIX, it is tied to your transactional bank account. If you have multiple bank accounts and you are banned by one bank, your account on the other banks are not automatically banned and you can still transact with it, I would imagine PIX would still work.