Because if it is uneconomical to rent out, there are few units available to rent and the few that are are super expensive. And the property won't be maintained properly. These unintended consequences ultimately hit tenants.

In Paris there is a similar impact of bad regulation. It has become so hard to expel a tenant that has stopped paying that landlords will demand extraordinary guaranties: bank credit lines, guaranties from relatives, sometimes even medical exam, etc and will be super picky. I knew of a foreign investment banker, high salary, not allowed to get in financial dispute because of his profession, who just couldn't find a place to rent in Paris because he couldn't provide some of those.

Because it is hurting the would-be renter group even more?

I personally know two people who are renting rent-controlled apartments in SF and don't live in them. Their lives have moved elsewhere and they don't need the place anymore. One uses it as a weekend getaway and the other one visits rarely.

Thanks to rent control their rent is so cheap that it's worth hanging on to it even though they don't live there.

So these two units are off the rental market effectively forever, sitting empty most of the time.

Because landlords start being unable to afford repairs, and you get a bunch of decrepit buildings falling apart all over the city (with all the dangers that implies, not just to occupants, but to nearby buildings as well). It happened in my home town, and it wasn't pretty.

Landlords are not social security. It's probably better for the city to forcefully buy them out and create a new management model of the buildings than to impose strangling limits on prices.

Because the result is that small landlords who can't deal with the fixed costs hassles simply sell out and consolidate into larger ones with more clout with politicians to weaken renter rights and legal resources to fight pesky tenants whom they simply don't want, or create shared blacklist databases like has been done in New York. If you're going to gird up for class warfare, realize that tenants are probably going to lose as long as zoning restricts your options

Wow, I literally belly laughed.

If a renter can't find a landlord to rent from, then what?

"Why should I care about the woes of water treatment plants as opposed to water drinkers?" Do you want drinkable water, or not?

Because shrinking the number of landlords shrinks the number of units available, raising rents, _hurting renters_.

Ok. Then care about the tenants. Do you have one shred of evidence that rent control, broadly, helps tenants? Because every economist I ever heard on this topic, left or right, argues rent control is bad for tenants.

Unless you have the capital to build your own house or apartment, you need landlords to put up their own capital to do that. It’s not like landlords are just assigned houses for free from the government to then lord over renter peons.

Because landlords supply housing and renters don't.

Why should I care about the woes of you opposed to me? Why should I care about the woes of the poor opposed to the rich?