PS I know this is one event, it was also part of a consistent pattern of similar events. The school administrators had no problem admitting this in public and were proud of it.
Was this true when you were a kid? Why do you think it changed? Because when I was a kid and a kid was bad, the teacher would make the parent come to class until the kid started behaving. Do you think this would work today? And why would some teachers be opposed to it?
If it wasn’t actually useful information, how would you know? How would you discover that?
As you say, it’s a bit of a black box unless you volunteer in the classroom (as my spouse did).