It's especially absurd since we're talking about a global, dynamic city, not some small rural town. Can you imagine if 1900s NYC had the NIMBY culture of present day SF? It would've severely choked its growth.
SF's saving grace is its VC ecosystem and network effect between existing talent. You can barely even say they have a monopoly on talent pool, since the ivy leagues and many other top schools are nowhere near SF. These factors are gradually growing in other cities, and the bay area will get to a point where the cost of living will turn it into just another city. They've essentially created one of the worlds largest funnels of money into landlords pockets. So much wasted capital.
This isn't like the finance stronghold in NY or entertainment in LA, tech companies are involved in every industry, and don't need to be in SF to thrive.