I'm not an economist, but it really seems like there's a very perverse economic distortion that takes hold when the relative wealth of a region exceeds a certain level. The problem is emergent from two facts:
(1) We almost always finance real estate on credit.
(2) We use real estate as both a store of long-term savings and an investment whose value is heavily leveraged and is dependent upon the value of neighboring real estate.
As a result, real estate acts like a sponge. When a region accumulates wealth beyond a certain point, it results in runaway real estate hyperinflation. This in turn forces people to put more and more wealth into real estate, as well as tempting people to engage in real estate speculation. This in turn feeds the cycle, and drives up rents for non-owners.
This does several bad things. It prices out the not-already-rich and destroys the engine of class mobility that often created the wealth in the first place, prices out artists and others who contribute to culture in a less financially-centric way, and soaks up wealth that could have been used more productively. Instead of founding the next startup, a significant chunk of money ends up sitting in real estate to prop up the leverage bubble.
Edit: I thought of what might be a more economically-correct way of saying that. Real estate is a liquidity trap.
Finally, it's a ticking time-bomb. If the region's fortunes ever falter, everyone ends up massively underwater. Bay Area residents be warned: Detroit once had the highest average wages in the USA. It was the Silicon Valley of its time. Detroit had other problems the Bay Area isn't likely to have, but some significant fraction of its woes can be tied to the collapse of its real estate market and all the perverse follow-on effects this has. When real estate starts to go south in a big and long-term way, it really ruins a region's finances.
P.S. I can't help but shake the feeling that the only winners from the above arrangement are banks.