it's not as if a small oligopoly owns all the land Not owns, but controls: the city (and residents) of San Francisco are the ones making the critical decisions

it's not as if a small oligopoly owns all the land Not owns, but controls: the city (and residents) of San Francisco are the ones making the critical decisions here, not the property owners. The property owners are playing rationally within the rules the city has set up. If they want a different outcome, they can change these entirely man-made rules at any time with the stroke of a pen.