If over regulation drove up prices, what exactly do you expect from more regulation?

It is possible for regulation to lower the cost of some things. For example, currently the regulatory environment in many California real estate market lowers the cost of holding rental property. In a more competitive, less regulated market, the opportunity cost of buildin developing now housing would be lower, so landlords would have more cost (indirectly through decreased rent or directly through more frequent renovations).

Hopefully this move leads relaxed zoning laws and regulations, allowing new development... People who want such things will gain political clout because capital will want return on investment, and rent control shifts the calculus for good ROI in the real estate market toward new development (marginally).

I'm sure hundreds of economists have written thousands of papers about this subject, each going its own idiosyncratic way, so maybe I've actually been proven wrong in this particular case, I don't know, but I have to say that the idea that regulation only ever increases costs is silly.

> rent control shifts the calculus for good ROI in the real estate market toward new development (marginally).

It does precisely the opposite. It reduces the value of rental properties, which makes investing in constructing them less competitive against investment in constructing new housing in some other state or country, or constructing commercial properties rather than residential ones, or any other competing investment securities.

To expand the set of people suffering to include landlords and owners, instead of having own group of people benefiting from regulation (in the form of restricted supply) and another not.

EDIT: to be clear, not suffering for its own sake, but to pressure owners to stop supporting the current regulations.

As long as demand for housing continues to outstrip supply, especially if demand continues to grow at a rate exceeding the growth in supply, then there will always be money to be made in housing.

This law in California allows for 5% annual increases after inflation. It’s hard to see how this will even hurt landlords. Creating a pretty clear incentive to perform a maximum increase ever year doesn’t seem great for renters though.