In my school there was little physical bullying. I cannot remember any to be honest. Psychological "terror"? Plenty. I am actually not that old, but 15 years ago it was mostly parents that mediated conflicts. Children are ashamed to admit they are bullied in many cases, so you need good teachers to notice and speak to parents.

I cannot honestly condemn teachers that disengage though. Classrooms get bigger, bullying happens digitally and out of reach, teachers and parents are critical of each other and pupils are the first to notice if they have free reign and know pretty well how to profit from such conflicts.