You can build out of concrete and use fire resistant materials like metal or tile for the roof and your house is nearly fireproof. These buildings would be realistically insurable in both California or Florida. They would cost more to build, not THAT much more though especially if land costs many millions, an extra 50k - 100k to build out of concrete is a very reasonable expense.
Just like exactly the rest of the world? We, the non-USA folks, are looking yearly at either fires or hurricanes destroying these wooden houses there and people keep rebuilding them. Insanity.
You can build wood framed (2x4, 2x6) buildings that are resistant to fire:
* https://www.youtube.com/watch?v=yZe-TlYxm9g
A stucco, brick, or fibre cement siding, have 2m/6' clear around the base of your house, tempered windows, and either a metal roof or shingles with a Class A fire rating.
You can make wood not burn on the kind of environment where it would be the only or main object releasing heat. That is still a completely different category from non-flammable materials.