Eh, that discourse is usually being advanced by people who never ride the bus, don't intend to start riding it, and have a personal interest in selling you a car. In real transit preference surveys, and historical outcomes, it is clear that people would ride a bus that goes to their destinations, comes often and reliably, and is reasonably priced, without regard to how many mental cases are aboard. So if a transit agency faces a choice of spending limited resources on policing the inside of the vehicle for lunatics, or adding a bus to the schedule, they should always choose the latter.

We take the bus all of the time here in DC. I’ve literally never once encountered someone like that.

I’ve been panhandled a couple of times (in as many decades) and there’ve been a few people yelling at each other, but they left everyone alone.

On the driving front, though, I’ve had a bunch of people with anger management issues threaten to kill me and the only times in my adult life that I’ve credibly been threatened with a fistfight were by people driving who resented being expected to stop for pedestrians in the crosswalk. The bus crowd is a lot more chill.