No it isn’t. It’s just unprofitable which means it can be fixed with higher rates.
Sure, but state governments (in the US) also set what prices are allowed (disclaimer: I don't work in the industry but have friends that do so I might misunderstand). And that means that if the state says "you can only charge X for insurance", and it's still unprofitable, those customers are effectively uninsurable.
I see that as a regulatory issue, but of course, the end result is the same. I'm familiar with services being effectively unavailable as a result of regulation from living in Canada. (Health insurance / not being allowed to buy healthcare).
There are to components, breakeven price for profitability and the price that an or will be paid.
If it costs 10 million dollars to replace a house, the insurance will be out reach for most homeowners.
My understanding is that some people are willing to pay, but it's illegal to charge that much.
There is an issue with price caps in some regions. Some of those have been addressed.
I think this is a subset of larger shift in the economics of insurance. While coverage focuses most on the climate change aspect, the majority of the change is driven by building costs. If you cant rebuild economically, then you cant insure economically.