One factor in the housing shortage that makes a lot of sense is elderly couples not willing to downsize for obvious reasons. My realtor friend was talking about this, he has clients who want to downsize, but basically can't. It has naught to do with zoning. Obviously, there are financial factors for younger couples that zoning won't and can't help. This is why the couples around us are renting at $3 K a month, broadly speaking. They have plenty of income, but can't manage a house.