They are right. If they don’t go, prices won’t go down as much. The reason simple, they’ll jump back in before it get’s back to fundamentals. Then hordes of people that waited instead of emigrating will jump back in and prices will rocket up again, then speculators will start watching reruns of “Flip That House” and the cycle will repeat.
Seriously though, California is not likely to see reasonable prices by national standards any time soon. The prices will be much lower than they are now, but for the price, you will still less than half of what you could get elsewhere, even adjusted for the difference in wages.