It’s true that you’ll probably see something unpleasant on public transit once in a while but most folks aren’t going to share the experience of someone who is literally tasked with engaging with and managing the people causing problems on the bus.
It’s unfortunate though because in my experience transit feels a lot more pleasant when there are at least a decent amount of people riding with you. When people start to feel unsafe and stop riding, it can drive further people away if they have other transportation options.