City of San Francisco is one of the exceptional ones since it secured the best water from Hetch-Hetchy many generations ago, and the worst that is likely to ever happen is bad pipes, and possibly contaminants in the specific areas that saw military use(i.e. Hunter's Point, Treasure Island, Presidio). Other towns in the Bay Area have something bigger to worry about, OTOH, even tech workers at the major SV campuses. The South Bay is dotted with industrial Superfund sites and there are a lot of unknowns about when and where they'll leak out.
You basically need to keep your windows open in SV. That and live up in the hills.
I don’t see why anyone anywhere would risk drinking tap water when filtration systems are relatively cheap.
Get an RO system and a water bottle.
SF water comes from Hetch Hetchy so it's probably ok. I would worry about lead maybe..