What would people do if, as you say, everyone gets into it just for the money? Would enough people consider leaving somewhere else?
(I'm just interested. It would be nice to hear more.)
Granted, I think it's more accurate to say that "tech" is the one doing the hiring and making people rich, not the SF Bay Area itself. But since this is the nexus of the (consumer internet) tech industry worldwide, I think its safe to say that a lot of that opportunity is found here