The California Department of Insurance regulates the insurance rates, down to how much they can raise them each year. Over the last decade the real risk of these fires has become better known to insurance companies and they've been screaming to be allowed to raise rates faster. Some have even exited the state completely (to new sign ups).

CalFAIR is the state insurer of last resort but last I checked it's not subsidized. There were talks of needing a possible bailout last year, and it's going to intensify now, but it hasn't happened yet.