Plenty of things were built just fine or better and hold up with regular maintenance or modifications, and many are proving to have only been practical to build during a time that had a lower floor for better or worse depending on the thing.

Would some places have become what they are today had they not built their subway system when it was opportune or hilariously less expensive than it is now? The good things we can iterate on or refactor now would have way more overhead to build from scratch at todays standards, not all of which are inherently useful or justified. Sometimes a whole city burns down or all the labor was forced, which sucks and we don't want, but sometimes you're having to get shadow studies done to build anything higher than a bungalow

> At the same time a significant chunk of the population works to defund and defang all government, preventing the existing rules and codes - labor protections, fire protections, food safety protections, etc. - from being adequately monitored and enforced.

This isn't helped by actual bad rules and regulations on the books. Some minor examples are the prop 95 warnings on every damn thing or the way CAFE standards work to encourage the sale of more pickup trucks. I don't blame some people for wanting to scrap the whole regulatory system after encountering enough of these.

People who go without insurance because they live in an uninsurable location would leave those who remain insured better off, because the insurance company would be less likely to need to make an exorbitant payout to the victims in the disaster-prone area. This is of course true as long as insurers don't manipulate the market to keep premiums high despite their total expected claim outlay lowering.

As an insurance buyer, in a hypothetically ideal market situation, you would want all those who also purchase from the same insurer to have the lowest risk of needing an expensive claim paid. The lower the expected payout * risk of disaster means lower premiums for the insurer to still make an expected profit.

I think what will happen is simply: Houses are built in places which are more insurable, existing danger-prone houses will exist until they are destroyed, until then they will increasingly be status objects for the elite who can afford the loss and have inaccurate risk appraisal. The fact that so many valuable objects are kept in Malibu/Palisades homes despite fires happening there a lot (as recent as 2018) indicates homeowners in disaster-prone areas aren't acting perfectly rationally.