I too believe it's mostly political. If some hypothetical SV startup invented a shoebox sized device that cost $100 and when sprinkled with water would unfold into a multi unit residence, we would still be faced with a ton of other issues relating to zoning, particularly density and parking requirements, that would continue to make housing prohibitive.

Also, Americans have been sold on the idea of real estate as an investment and I'm not sure how we will ever get policies that lead to lower housing prices when that essentially means that a large part of the population will have to agree to enact policies that will result in depreciation of their primary asset.