Public transit connections to SFO are shit-tier. Rideshare prices have little to do with it.
You can BART from there to downtown, that beats a lot of cities. (yes, yes, BART quality can vary, but still.)
What about the rest of the Bay?
I've taken BART and it's fine but expensive (there's an airport fee that's something like $8 per ticket each way). For groups/families I could see rideshare winning on both cost and convenience.