The maximum rent increase rate is 60% of the trailing twelve months CPI in the bay area. But landlords’ costs do not scale with the CPI. Mortgage rates are fixed (if a landlord has a mortgage at all), taxes are independent of CPI, and principal+interest+taxes are the vast majority of a landlord’s expenses. Maintenance is typically a small fraction of that number.

Landlords are not obligated to pay your heat or water under rent control. Mine certainly never did.

The roommate law changes you mention are not rent control, but tenant protections applicable to all rentals in SF. The 2015 change brought rent controlled units up to par, because landlords were evicting people for doing things like getting married or switching roommates (horrors!) Basically: preventing predatory landlords from being scumbags.

I’m going to go with the GP on this and say that if you think people should have their rent hiked for getting married or changing roommates or having a kid, you have poor morals.

In essence, you don’t like being told what you can do, you have a theory that it hurts the housing market, and you’re inventing reasons to justify your theory of reality.