Limited yes, but limited by regulation more than anything else. Within a 30 minute drive of SF there are hundreds of square miles to develop on. Pick a dozen at random and build residential skyscrapers. Problem solved.
Edit: SF itself does have strict zoning. But even if everyone there wanted max density, so they tore everything down and built skyscrapers instead (ignoring the soil problem there), it's a fixed supply of land.
The apartments are still quite expensive even an hour’s train ride away.