As a regular public trans rider here in KC, I keep my head on a swivel. I've ridden for years and have only had two dangerous close encounters with homeless people, but as some have said, it's unlikely surveillance will do much to change it. You're probably more likely, statistically, to run into danger driving or riding in a car. (Note that our streetcar line does have armed security though, so that's nice.)

It's security theatre and the footage is probably being sold to train someone's AI model and sent to the fed without a warrant to tag to the profile they have on you.

That said, I carry a stungun for my personal defense, but I 100% would not use public trans habitually without some means of self defense.