Yep. I live in SOMA, near both the freeway and a BART station.

Without traffic, a car has me (and a friend) curbside in 12 minutes for $30. Even during rush hour, the southbound traffic between the 7th St onramp and the SFO exit is almost never very slow (while NB is always a standstill).

BART is 30 minutes on the train + however long it takes to walk to the station + the transfer from BART to SFO AirTrain to get to the terminal. Minimum 1 hour. Easily another 30 min if you're unlucky with train arrivals. And by getting off BART at the airport stop, you pay a premium fare of $11.80 per person.

I simply don't bother taking the train.