Insurance premiums. When the reinsurers give up the game is over, and that may only be a couple more catastrophic hurricanes away.
When the reinsurers won't backstop the insurers, the insurers have to decide whether to gamble and offer massively high rates, hoping that they can accurately judge rate payer demand, and knowing that they could get screwed at the next catastrophic event, or just GTFO of the market all together. Insurance companies tend to be conservative, what with all their actuaries, so bet on the latter.
Then all the big money in real estate starts to get out and that whole Ponzi scheme starts to collapse. When it happens, and your home is worth essentially nothing, and you don't know how you'll afford to fix it if it gets wrecked in the next big storm, what does Florida really have to offer beyond the services that support its population? Disney? I understand that the citrus growing industry has been hit by some sort of plague (it would be interesting to know if that is climate related), and the other ag-related components can't be that large compared to other states.
I guess the US government could backstop catastrophic events with more insurance, but at some point we need to say no and acknowledge reality. We should be encouraging people to get out of these areas sooner rather than later, and maybe even offering incentives to do so. Blue states should definitely not be subsidizing more irresponsible behavior from people like governor Fab Boots Desantis.