You're assuming a fair and rational market. These clowns are actively rigging the market. My city has very high commercial rents despite less than 50% occupancy with two feudal dickheads running the show. Businesses are having to close left and right. Apparently the banks will get mad if values drop and the the whole market will collapse, and that's apparently "bad", despite this being exactly what should happen in a fair market, and exactly what we need. It's insane how much we've allowed these assholes to derisk.

building housing units is the only way to lower housing costs

this person never heard of abolition of private property

Corporate landlords got caught using an app on people's phone to collude to price fix rent. They have settled, but there is very little incentive created, because nothing made it to a court decision, to stop this behavior. So yes, they do raise the rents whever they want, because they have coordinated with every other in the region to have similarly over blown pricing.

That proposition is not about restricting housing construction.

How would it be vetoed?