Semantics
PUBLIC ENEMY #1
The play was a bad elbow to the head which resulted in the Eerie player being banned indefinitely. A stupid kid did a stupid thing. It wasn't an injury because Marner is 5"11 or plays hard, it was a violent play that would have taken anybody (size regardless) out. OHL or NHL makes no difference in this case. It's just something that happens. It would have given McDavid a concussion as well.
The only silver lining is that kid seems far less talented than his dad, so the odds of him making the NHL and terrorizing people's knees is very slim. And he's 19, so hopefully that was the last game he plays in the OHL.