True.
But a non-political solution to affordable housing could be coming soon in the form of rapid transit via Hyperloop. Hyperloop could put deflationary pressure on housing prices.
If Hyperloop actually materializes, and their route transit times are anywhere near what they say they will be, then real estate prices should decline in the bay area, or at the worst level out.
I doubt people will continue to pay crazy prices in SF when you can commute from almost anywhere on the west coast to SF within an hour on Hyperloop.