This has been my point for the last 5 or 10 years. That's why I have a "home phone" with banking apps, 2FA and important stuff installed. It has no SIM card and never leaves home. For everything else I have my "street phone".
Many banking apps require a phone number/SIM card to operate, but assuming you can copy codes, etc, what happens when you want to use those apps out and about (or abroad) if the phone never leaves home?
Fortunately, my lifestyle places me out of that use case.