I have this requirement too, since I like to use F-Droid.
My point isn't that there are no such users. My point is that product managers in banks don't care about F-Droid users, since there's so few of us that it's not worth them worrying about.
Many websites are giving up Firefox support, and Firefox adoption is much higher than F-Droid.
If a bank app happens to be okay with F-Droid, it's not because they look out for the needs of F-Droid, it's simply by happenstance.
> If a bank app happens to be okay with F-Droid, it's not because they look out for the needs of F-Droid, it's simply by happenstance
Not true. They they have to make a deliberate choice to write an app that refuses to run if you have installed non-Google apps. It needs code written to run checks. It even lists the apps I have.
> Many websites are giving up Firefox support, and Firefox adoption is much higher than F-Droid.
Not hat I have noticed.
I definitely stay with my bank (Lloyds in the UK) partly because they have a good website, and I will not bank with HSBC because their app will not work if you install things from outside the Google App store (and logging into the website needs the app, at least for me at the moment - I think that can be solved).