Even in places where hurricanes and earthquakes are common they put electric lines on wooden poles with the result that when an earthquake occurs or a hurricane blows through the streets are literally covered with downed power lines. I live in an earthquake prone region where we almost exclusively use underground wiring. We've never had an outage because of an earthquake.
And I lived in Los Angeles and never had an outage because of an earthquake. Had many earthquakes, including some pretty big ones that destroyed a lot of buildings near the epicenter. I now live in a place that sees a major hurricane every 20 years or so, and got to experience that firsthand.
Anyway, we put the wires on wooden poles for three reasons:
- 1- We have a shitload of wood. That makes the poles very cheap.
- 2- They're pretty fast and inexpensive to repair.
- 3- We've got a lot more distance to cover. So we've got a lot more power lines and burying all of them costs a lot more.
The power lines usually have enough slack to deal with the earthquake itself. Something falling on the power line can obviously cause a problem, but that's not likely to happen unless you're very close to the epicenter and it's a big earthquake.
In hurricane prone areas, new construction usually requires the bottom floor to not be living space, and it's usually built in a way to resist flooding. For example, the building is actually on pilings and the bottom floor's walls are built to break away. However, that's new construction. We've got many decades of old buildings still out there. When you've got places that regularly go 60+ years between storms, it's going to take a long time for the old buildings to be "forcefully upgraded".
As for wood construction, that remains popular because we have a shitload of wood. Building out of concrete is vastly more expensive. And when it comes to earthquakes, wood buildings tend to do better. Wood can flex, versus a concrete building cracking under the strain. The main problem becomes sufficiently anchoring the wood to the foundation, and a tough enough foundation to withstand the shaking.
As for your comments about New Orleans reconstruction, many of the areas are so far below sea level that a single "flood safe" level isn't enough. The house would have to be built very high to keep it above all potential flooding, which costs way too much for an event that is unlikely to repeat for a few decades. And in theory the levees are supposed to prevent flooding to begin with.