Ultimately, I don't think the most important challenge is in binary firmware blobs, but the software which people depend upon to run their lives. What does it matter if you can run a completely free software stack on your phone, if your bank software (or your required government ID, as is looking depressingly likely) requires you to run a Big Tech approved phone OS? Perhaps the FSF can't do much about that, but that…
In an emergency, can't you call your bank over the phone? Do you depend on it still if you have a Computer?
I tried calling Starling Bank in the UK when my phone screen stopped working. I assumed they would have basic phone banking service.
They told me no. The only service they could provide over the phone was registering a new device to resume access to bank services via their mobile app.
Although they have a web banking service, which can he used on a desktop, that requires authentication via the mobile app too. It's not TOTP, it's their own thing.
As I needed to make a transaction, I had no choice but to buy a new phone in a hurry.to do it.
Several people suggest switching banks and credit card services, but I've found that not so easy. I have accounts with several banks (some for business), and 3 of them require use of their mobile app. Most credit card services I use also require use of their app. Some have websites that hand you over to the app at some point in the flow.