That's also kind of a pigovian tax though, right? By making gasoline more expensive they discourage its use. I guess they're chicken to make it an actual tax

Also why wouldn't it come from other US states? Seems easier

Pipelines, the Jones Act and CA blend requirements prevent CA from getting much gas from other states.

Sadly, it does not come from other states. It comes from other countries which, amazingly, tend to have much less strict environmental regulations.

Yes, California is a little cleaner because we have fewer refineries and gas is more expensive, but globally we are probably about even.