I have a degoogled phone (LineageOS) and I was able to get my banking apps working by isolating them in a work profile using Insular and also putting MicroG and Aurora Store in there. MicroG tricks the apps into thinking you are connected to Google Play Services. IMO its better than having a 2nd or 3rd phone.

All apps collect some information. Piefed requires your email to sign up.

I don’t want the free petition websites online getting my personal network’s info and sharing or selling it, hence the interest in self hosting.