This is a giant transfer of wealth, LA, SF, SJ will all see their housing prices tank, as people who can't afford cars are expected to move to suburbs where they can park a car.
SF OTOH has been pretty navigable with public transport plus Uber/Lyft. I try not to go there lately, for obvious reasons, but when I did I could get around there without a car without too much trouble. Having no flexible option (and taxis sucked before Uber rose and I'm sure will continue to suck after) would make it much worse, but I expect SF prices to drop anyway - people are finally realizing they don't have to pay 3.5K/month for a studio just to work remotely anyway. Golden Gate park is nice but not that nice.
Also wait and see what they do post election. The outcome of Prop 22 will decide what their true response is, until then this is just grandstanding to force voters to vote yes.
And anyone that can afford a car probably has one, and anyone who can afford to move to the suburbs and live with the hellish commutes already has.
I don't think this changes anything about transit in LA.