At this point, I think SoCal may just be cursed. Horrible traffic, smog from wildfires, a tropical storm, and an earthquake?! I think that should be a cue to move out before the LA river turns into blood or frogs start raining from the sky.
Ps not judging here, I'm just qualifying :) I'm from the Netherlands, from a part that was most decidedly below sea level which is also inviting disaster obviously. Especially with the rising sea levels. And one huge disaster also happened in the past.
We also have an entirely human caused earthquake problem in the northeast due to the empty spaces left by natural gas extraction.
Out of curiosity, are household-level defense measures at all common? Personal flotation and/or small boats, means for rooftop access, or such?
I will guess there can be cultural differences vis-a-vis fatalism and lack of preparation.
I feel like we've got more trust in the government than people in the USA do too. I fully expect that if the dykes do break the government has a rescue plan in place and a playbook on the shelf ready to get dusted off.
After the 1953 North Sea flood a lot of things happened to make sure such things would never happen again. To quote a monument on Eastern Scheldt storm surge barrier, part of the delta works: "Here rule over the tides the moon, the wind, and us."
It's part of the north (mid / east of Groningen province), that has an earthquake problem.
These are mostly minor (like ~2 on Richter scale), but frequent. Causing structural damage in many (mostly older) houses, and people losing sleep over safety, house value & damage compensation. Imagine feeling minor quakes weekly, and seeing new cracks appear in the walls of your house every couple of months.
Cause of these quakes is man-made: natural gas extraction from Slochteren field. This field is slowly being closed, and subsoil will settle eventually. But that process is measured in decades. So quakes will continue for years.
Most houses affected by this, were built before Slochteren gasfield was even discovered, and earthquakes in this area didn't exist. So those houses' owners can't be blaimed for the problems they're having. Nor were those houses built with earthquakes in mind.