In theory? In practice and when I have a choice, I will always pick mass transit instead of driving because I prefer to walk and avoid the hassles of traffic lights, risk of crashing or running someone over, wear and tear on my car, gasoline, etc...
I'm going to guess you've never had some drugged-up crazy try to stab you in a bus? After the second time it happens, you never ever consider it again. Life is too short to die like that.
One particular example that had a good breakdown: https://digitalcommons.usf.edu/cgi/viewcontent.cgi?article=1...
(If nothing else, the piles of corpses would, presumably, be noticeable and cause scheduling issues.)