The reports I remember from years ago (circa 2010 or 2012, forget the exact year) were that the city wants to build Treasure Island up to support about 30K people, give or take. The renderings were pretty cool, till you consider the stability of the ground in an earthquake, the radioactive waste and rising sea levels.
This was shortly after the plans for what would become the Transbay Transit Center[1], the Salesforce Tower and the Millennium Tower were approved.
Make your case though, why ditch earthquake restrictions?
[1] https://www.nytimes.com/interactive/2018/04/17/us/san-franci...
Seriously though, I was reading just yesterday about how they're developing Treasure Island and it has a high chance of liquefaction (not to mention radioactive waste) because demand for land is that high.