I'm not arguing with you nor rebutting your claim. I haven't studied the situation in California and have no opinion about what is going on there.
But I did work in insurance for a few years and insurance began as a form of betting or gambling. If the possibility of X happening is too high, it's no longer a gamble.
So as the odds of being required to payout approaches 100 percent, they stop covering it because that's not what they do.
This is why flood insurance in the US is provided by the federal government, not private insurers: Because most land with residential development floods. It's not a question of if but when, how often and how badly.
Hurricane Andrew also significantly impacted the homeowners insurance industry. I don't recall the details at the moment, but this is not without precedent.