If the hilly San Francisco can have lots of bikes and buses (…and cable cars and street cars and light rail and commuter rail) then so can most cities.

SF is compact, and has a few main drags where it makes sense to have trollies / bus lines. It also has a well-defined city center, so a hub and spoke transit system mostly works there.

In contrast, public transit doesn't even really make sense in South Bay. It was (mostly) laid out when public transit was common, but now there are multiple mini-downtown areas without train service, and many of the tracks have been ripped out.

But downtown doesn’t need bikes. There’s amble public transit and everything is close by. Most people I know who bike use it for longer distances, eg the base of Bernal Heights to downtown via mission+market. Or going from Caltrain to sunset.