Low participation doesn't excuse someone from being crappy at their job.
Kind of ironic in this day and age when everyone is concerned about player safety, there is so much support for an official that missed an obvious call on a dangerous hit.
Except it's not obvious from the angle of the ref. It's obvious from the camera angle, which is the exact opposite side. Remember, it's only a 5-man crew, the white-hat is the only one watching the QB. The defenders head is behind the QB. He sees a hit, has 1/4 second to assess what he saw. He made a mistake, sure. I agree, it should have been flagged for targeting. But it's a very difficult call to make (I don't personally know him or anyone involved).
I can almost guarantee you that the head ref from that game is beating himself up for missing that call.
If you are saying, for the sake of player safety we should move to 7-man crews for varsity games to get more coverage on this type of thing, I would agree with you there.