there’s plenty of half empty apartments all over soma and mission bay
If it’s set where it’s cheaper to hang onto the vacancy until rents rise again and finish the build then, it’s a problem.
i tend to favor vacancy tax, but this won't fix the problem with developers. SF needs to reform their review process. this is TLDR but there was a big study about this: https://www.nytimes.com/2023/10/25/us/san-francisco-housing....
it's already incredibly expensive for a developer to even go through the review process for a development, let alone build it. a vacancy tax would further deter developers from building in SF (as it's already happening due to the terrible review process)