Is the world becoming uninsurable?

Not uninsurable, but buildings are going to have to become tougher.

It's happened before. Chicago's reaction to the Great Fire was simple - no more building wooden houses. Chicago went all brick. Still is, mostly.

The trouble is, brick isn't earthquake resistant. Not without steel reinforcement.

I live in a house built of cinder block filled with concrete reinforced with steel. A commercial builder built this as his personal residence in 1950. The walls look like a commercial building. The outside is just painted cinder block. Works fine, survived the 1989 earthquake without damage, low maintenance. It's not what most people want today in the US.

In Yugoslavia, in 1969, one of the biggest earthquakes occurred, destroying several cities. After that, the country’s leaders decided to change building codes. Even today, although Yugoslavia no longer exists, the countries that adopted those codes have homes capable of withstanding earthquakes up to 7.5 on the Richter scale.

My main point is that if we face major natural disasters, we need to take action to mitigate their impact in the future. As a foreigner, it seems to me that Americans prioritize building cheap homes over constructing better and more resilient ones.

Why bother building a better home when it's cheaper to buy insurance and rebuild later?

This is why prices are important - sometimes it's sensible to build cheaper houses without these safeties if the risk isn't there, but if the risk does exist then it needs to be priced right to provide that incentive.