Comment by epistasis

Rent control also switches the class politics, as people who are paying far below market rate for housing become like landlords and homeowners: getting free imputed rent.

People have been knocking down doors to build in SF for decades, but do not because regulatory capture by homeowners, landlords, and those with below-market rents are happy to keep out new people.

Where and when housing gets built in the US is not merely a market driven decision: you also need to get local permission to build.