Moving elsewhere can be difficult, very much so, but not learning from things of the past?
The ignorant masses of humanity don't know anything about the past. If they weren't around to witness it first hand, didn't happen as far as they are concerned.
I live in a first world western democracy with very high scores in most development metrics and I can find people living on my street that don't know Canada is a real country (I can see Canada from a step ladder), think the USA was contemporaneous with the Roman Empire, have no idea the film Titanic was anything other than fiction, and believe the world is flat. Most of these people have more money and went to better schools than I did. The poor (80% or so of the planet) are even more frightening in their ignorance, but at least it's not their fault.
But srs. Why build above ground (where hazards are happening in almost clockwork fashion) when can go below, and with suitable setting flooding of said underground can be avoided, too.
In a place like New Orleans (one of the more prominent examples I was thinking of), not even graves are underground because the city is twenty feet below sea level and the water table is a foot below the ground. The result of Hurricane Katrina was a wholly foreseeable, predominantly man-made, disaster that occurred less than fifteen years ago, and is already starting to be forgotten...because that's easier than dwelling on it. Those with the power to make meaningful changes do not care about those who wouldn't have a choice either way.
The next big storm in the area is going to be a repeat of 2004, as will the next one after that, until there is simply nothing left to come back to, or no one left to return.