I don't think this is the case here. Like, this is dead on arrival in most of Europe without WhatsApp. My phone is my most important device. I cannot access my bank account without it. But banks will not allow me to use that phone as a factor for authentication.

5 or 10 years ago you could have forced those companies to either support something third party or develop for a new phone os but now we are stuck with android and ios until something really messed up happens to our economy or until one of them really fucks up and gets into legal trouble to a point where they can't sell phones or services anymore.