See, that's what I mean about sensible applications of rent control. Having a small class of rent controlled appartements is silly and it's not something you ever want to do, it's only ever a terrible compromise between politicians and landlords that everyone knows is a bad idea.
It doesn't suppress supply when building is already wildly profitable and is just being slowed down by permitting either.
The negative impacts of rent control have been the subject of literally hundreds of empirical studies. It's a known quantity at this point and, when you quantify the impact, it's generally worth it, especially in our current zoning hell. It also helps with price stickiness once supply does increase : as you know, developpers only like to build upmarket appartements, which typically take a decade or more to trickle down to the average person.
The main thing is not to do silly things like only apply rent control to a small portion of appartements, we know it doesn't work, and to allow rent to increase with any reasonably incurred costs. This way you actually incentivize landlords to repair their apartments, you reduce the mobility risk, etc...