If you look at the data above it shows home building peaking in the early 1960s in NYC. Rent control laws were strong until the 1970s. That's the point when homebuilding plunged and didn't perk up for decades.

Weakening them in 1974 if anything seemed to restrict supply.

SF has comically low density housing that is driven by homeowners lobbying to restrict development.

The difference between SF and Seattle is probably property taxes (higher in Seattle). It discourages land from being hoarded and used unproductively.