No one ever said it's up to the consumer, it's up to the market. Granted, California banning them isn't the market, but the bank not offering loans is.
Consumer demand -- or lack thereof -- drives the market. There have been massive product flops in the past... no level of supply or price cuts could get consumers to buy items they didn't want. I'm not saying that's the case with electric cars, only that consumers have to want them before it can succeed.
Consumer demand is shaped by credit availability. Regardless, the issue with electric cars right now is almost entirely supply constraints, not demand. You have to wait months or even over a year depending on which particular car you want.
Banks would only stop offering loans if required by law to stop, how is that different from a state or federal ban?
No, this was a bank who said they would stop offering loans for gas/diesel cars because of their corporate stand on environmental issues. It's only one bank for now.