[rtpg]

Because then things like restaurants downtown would have more foot traffic during lunch time to help make sure local businesses don't shut down. Also, it could help make downtown "bigger", so even if the end result is the same (higher rent), there'd be more apartments available (instead of the suburbs that take a lot of space for not many families).

[macspoofing]

I'm pretty sure the San Fran downtown is already in-demand, and as I said before, you can't have everything.