What banking business? Use a web browser, or just bank in person like everyone did not long ago. Carry a credit card instead of Apple/Google Pay. That's what degoogled Android users do and it's a very minor inconvenience anyone with a little bit of maturity should be able to accept. Also, cash is much better for your privacy.
It’s not possible. Logging in to a banking website is becoming strictly speaking impossible w/o a phone.
Or instead of hamstringing your entire way of life and making things immeasurably harder.. we could regulate them too.
And if you require a one-time SMS code for purchase (which can be adjusted via their website, most likely), then you still have an option that is not Apple and Google. I use a dumbphone for "banking" (SMS)... and a credit card, and the website. Those are really all the 3 things I need to do banking, as you have said so correctly.