Population growth is reduced by a housing shortage because people who otherwise want to move in can't if there aren't units available for them to move in to.
Moreover, who is supposed to have a monopoly on housing in San Francisco? Is there any single entity that owns even as much as 1% of all the housing in the city? And even if there was, wouldn't building more housing still fix it, because the more you build the more you dilute their monopoly?
The title of the link indeed says "the majority of the San Francisco Bay Area" but it also says that the largest of them owns 293 buildings, so for twelve times that to be a majority there would have to be no more than about five thousand total properties in the San Francisco Bay Area.
Meanwhile the Chronicle says there are about 2.3 million total properties, I couldn't find them repeating the claim that those 12 landlords represent a majority but they did say that "this list of 12 includes some of the region’s major power players in residential real estate, housing tens of thousands of families". Which I wouldn't expect to be a majority of the >7 million people who live there.
Moreover, who is supposed to have a monopoly on housing in San Francisco? Is there any single entity that owns even as much as 1% of all the housing in the city? And even if there was, wouldn't building more housing still fix it, because the more you build the more you dilute their monopoly?