Frankly I think it's a lost cause and sadly doesn't make sense to waste energy on it anymore. I eventually abandoned my de-googled phone exactly because I couldn't use my bank with it.
(One exception, I used to scan checks five years ago, but thankfully that finally ended.)
1. Transfer money to another account. The alternative is to waste half a PTO to go to the actual bank (because they only open at working hours) to make that transfer.
2. Make an online payment. Most new cards no longer have a CVV (3 digit code) and instead require you to use the app to get a dynamic number. Many banks do not offer that option in their web app.
3. Forced 2fa for in-person payments with your card.
Today it's still possible to workaround many of these issues but they're closing these workarounds little by little.
I'm curious what people need a bank app for.