Or not? I remember when banks required you to have IE long after nobody was using IE. I remember when banks showed an alert against using Safari long after it became the most common mobile browser. Banks also have their own apps and are not dependent on Chrome.
That was in a time when expectations were low and all the banks were pretty equally crap. There are better choices now, and even my mum would be pissed off of her bank website didn’t work in her current browser.
Would she be pissed off at A) The bank? B) The browser? C) The computer? D) Her internet provider?
People can change browser more easily than changing banks. They can even have multiple different browsers on their machine, and one for only doing banking.
For many people, the icon on the desktop they click isn't important. They just know when they click that icon, it brings them to "the internet". If she's one of those people, my guess is she blames the bank.