This is regrettable, but consumer options will slowly but surely force the larger banks to play ball.
I think those banks that deny service to crypto companies are just giving up their business to those that will. I recently set up a business entity around my crypto investments and one bank--a well known one that we'd used personally--flat out refused to open up a business account for that entity. So off I went to another bank (also very prominent, but not one we'd used personally) and I've been very happy with them ever since. I'm not sure what the upside was for the bank that refused. It's not like they were going to bail me out if I made a bad trade and lost money.
You're absolutely right! Eventually digital currencies will become more mainstream and the majority of banks have very little reason to exclude those utilizing or trading crypto. They do take the stance that it could be used by bad actors... but they accept cash if I walk in to make a deposit, which is far more advantageous for bad actors and far less traceable. The government even accepts crypto, at least in some states.