I think you're focusing on the wrong thing and missing the point. Housing supplies have not significantly increased with population growth (demand) in decades--thus the price equilibrium has moved up. I don't care if you build up or out and neither does the law of supply and demand. The left gets all hung up on 'the right kind of housing' and doesn't realize they're part of the problem--making it harder to build housing (of any kind) is pushing housing costs up.