The real problem with "never live on a floodplain" is that you can't know where the floodplains are. The flood maps are all based on historical rainfall data, and that data is now obsolete. Even worse, it won't stabilize in our lifetimes. So we can't just observe the next ten years of rainfall and plan around that. No, things are changing, and they will continue to change. You might think you don't live on a 500 year floodplain. But the cold truth of it is, we no longer have any idea where the 500 year flood plains are anymore. You need decades of weather observations of a stable climate to come up with accurate flood maps. And we just don't have that kind of reliable data anymore. Unless you happen to live on the top of a very tall hill, you really can't be sure you don't live in a flood zone of some sort or another.