Tenant laws hurt availability as many people keep units off the market because the law puts such strict limits on landlords that it can become abusive. There are many horror stories in SF about tenants from hell.
First off, rent control doesn't apply to apartment building built after 1979, so, as noted below, its less relevant - especially with the new construction in SOMA.
Second, the anecdotal stories about landlords holding units off the market is just that - anecdotal stories. The owners of those buildings are Prop. 13'ed with a 30yr old assessment and are doing just fine. Opening a new unit means they can collect more rent at todays market rates. Its a silly story promoted by landlords that would like to make more money during the booms. Of course, its also those very rent control laws that protect landlords during the busts (2002, 2009, etc).
Sorry to say this, but rent will come down when companies in SF start running out of their free, investor money and have to turn a profit or sell themselves. More people will lose their jobs, won't be able to afford living in the city proper and people will move away. Thats the way it has been here for at least the last 20 years and probably longer.
By the way, also anecdotally since I can't find the reference, rents in the area have decreased by 5% on YoY basis.