Your points are of course valid but this is getting slightly offtopic.
If your bank really spies on you through its app, I would change bank
What would be nice would be not to have to use a proprietary app on a closed-source software stack in the first place, given that it clearly represents a privacy compromise. And that is possible: almost no bank makes it obligatory. But they would obviously love to. If only to fire their web team and save some money.
And this is not just about banks. Every online service is trying to force us onto the closed platforms of Google and Apple, when an open-standards software platform exists and is perfectly workable. Seems there might be a battle worth fighting here. Nobody much seems to agree. Fair enough.
Just let your password manager fill up the login everytime, it’s not hard.