I live in the Bay Area, and I think this needs a little more exploration. You are correct both in that PG&E spreads the costs around the state, and that San Francisco (and a number of other Bay Area cities) is exploring creating it's own utility and removing itself from PG&E (like Palo Alto already has done).
It is a near certainty that power rates would be cheaper for these cities if they removed themselves from the PG&E pool. Right now they look to be on the hook to help pay for all of the (long deferred) power line under-grounding that the recent state wildfires have proven is necessary. Much of that under-grounding is to get power into remote locations, and does nothing for most people (other than the implicit reduction of wildfires, which is a complicated subject).
But there is a second side to that coin: without the big cities full of people (which are relatively cheap to service), all of the needed under grounding costs are going to fall to rural California areas, and they simply don't have the population or finances to pay for that.
Personally I am in favor of some mixture. I would make the utilities all completely non-profit, with no investors to demand returns (the current system has perverse incentives). I would also start looking at some drastic limitations on where the public pays for power lines. Yes that would make some rural locations financial impossible to draw power to, but that would probably be a part of a real-plolitik re-evaluation of where people can afford to live. This is probably going to line up pretty closely with pushing people out of fire-prone places that should also be pretty much un-insurable anyways.