I think the point of the law is to paint a picture of where we want to go as a society (of Californians). It’s 15 years away, so these things are more a signal that “hey this is where we’re going”. This in turn makes you think “hmm maybe I should buy electric” which in turn makes manufacturers go “hmm I guess we should go electric if we want to sell in California.” Its a self fulfilling prophecy, a mission statement and a confirmation of what we already know: electric cars are here to stay, they are likely to improve massively over 15 years, and they are the future of transportation for CA.