It does mention that it has a strong elasticity for demand. Particularly higher for medium+ income. Since its very hard to measure future elasticity of demand (i.e. SF now known to be expensive, if housing was built agressively and it became "famously cheaper" demand could be even higher) its possible that prices wouldnt go down much.
The correct answer to the OP's concerns is that the goal is not to lower rents, but to increase the total utility: you do that by providing more and better housing. New buildings at same rate for the same amount of people is still better. And naturally, same rate and more people is also better.
There's no doubt that San Francisco needs a massive shock to the supply curve.
It does mention that it has a strong elasticity for demand. Particularly higher for medium+ income. Since its very hard to measure future elasticity of demand (i.e. SF now known to be expensive, if housing was built agressively and it became "famously cheaper" demand could be even higher) its possible that prices wouldnt go down much.
The correct answer to the OP's concerns is that the goal is not to lower rents, but to increase the total utility: you do that by providing more and better housing. New buildings at same rate for the same amount of people is still better. And naturally, same rate and more people is also better.
There's no doubt that San Francisco needs a massive shock to the supply curve.