So the point is that in a super tight housing market, it doesn't take that many outliers to have a big effect on housing prices. Obviously I'm aiming at fairly high-end developers--like people with Ph.D.s or a decade of industry experience. But there are tens of thousands of people like that in San Francisco. And I've seen google, facebook, salesforce, vmware, and the like offer unbelievable compensation to these people when I'm trying to hire them.
The pattern is such that I don't think people are lying. In some settings, lying about offers could be a way to get leverage, but these people are not trying to negotiate--they know a small company can't offer those kinds of salaries, and do not ask for a counteroffer.
That said, note that I am not talking about salary, but "total compensation." Obviously prospective employers have an incentive to paint as rosy a picture as possible about that. So the base salaries might be even slightly under $200K, but with hefty guaranteed bonuses for the first year or two plus stock grants worth in the hundreds of thousands of dollars even if the stock stays flat.
Another way to look at this is that the housing market is a function of three things: income, interest rates, and the fraction of people's income they are willing/able to spend on housing. So obviously interest rates have been super low recently, and maybe people have increased the fraction of their pay they spend on housing--but that still can't go above 100%. The main driver of the San Francisco housing crisis is soaring income (and of course inequality) combined with inadequate supply.