Slipping assault, violent acts etc under the rug is incredibly common from my experience. Even regular cases of bullying, schools will never intervene and if they ever do, it's largely very surface level i.e. telling the bully "don't do that again" etc.

Also, the way the consequences of school intervention works is bonkers.

The bully is rewarded since they get suspended (that's a reward from their pov, not a punishment) while the victim gets punished since they get suspended (but now that's a punishment from their pov).

This is entirely normal from my experience and perfectly acceptable from the schools at least. Not sure it's acceptable by parents just yet.