Doing better than SF at building housing is a pretty low bar. I see no evidence that the high-demand cities that are building more housing are building it at a rate that keeps up with demand. As it is, what housing they are building is probably helping keep rent prices rising gradually instead of spiraling out of control as they are in SF.
Basically he's saying there are two tiers of housing consumers, and building dense condos does nothing at all for the lower tier who can never bridge the creditworthiness gap to get into them.
Of course time will tell.
A condo in a growing city is very liquid property and easy to sell.
Also, a lot of the condos being built - at least here in NY - are rental units.
The cities now housing more people now also support more economic activity, jobs, and development which makes the job markets even better, brings in more interesting opportunities and thus even higher demand. It becomes a more attractive place despite the housing shortage, and thus the demand grows even higher despite the supply growing as well.
The demand for housing covers both people who need a place to live and the countless other reasons people buy houses (an apartments/condos etc). They are a place to invest or park money. So when a bringing more supply online you have to be careful that it targets the correct demand.
Take a look at this pic to see vancouver's problem: https://images.app.goo.gl/uGmMJcwyNvXQUWdQ6
What do you think the real occupancy rate is of those buildings? 60? 70% at best? (They are all residential except for the few commercial ones, those with entire floors lit.)