Yeah I lived in Boston and never had problem with public transit, same in Europe. I guess left cost IS different and not in a good way.

How does this knowledge help me take the train safely?

I don’t know where you live, but in PDX it’s a hit or miss. If you go during rush hours on a work day in the suburbs, then you are mostly fine. Otherwise… You have high chances of being harassed by homeless people, spat on, threatened, leered at, smelling something awful. So yeah, not divorced of reality.