For less and less, presumably? Or is the housing situation so bad that prices rise even when the area will soon be underwater?
It doesn't even matter, really.
Suppose one person follows the sage advice of the HN glibertarians, sells his house and moves out. Good for him. But does this solve the problem? No, because now there's someone else there. Possibly a more desperate, poorer person. They can't all follow your advice, no more than they can all be best in their high school class, run the fastest in the marathon, or being on the winning side of a prediction market bet.
Yes but I feel a lot less bad for the person who sells there house and moves now than the person moving in. Basically what I was trying to show is that the option is still available and people are choosing not to take it so can we really act like they're all trapped in this situation.