I love shooting high-school sports, but one of the bad things that comes with the territory is that a few times a year I see a scene like this. (I normally don't take photos during injuries but made an exception this time.) This poor kid did something to his knee that was bad enough to require calling an ambulance.
As an athletic trainer (no longer "in the field"), the only time I ever noticed or was bothered by a photographer was when they would get too close. At the pro & college level, they had the glass - and we had security - to maintain respectable distances. In the high school setting, however, I was amazed on more than one occasion at a sideline/baseline photographer actually coming in close and trying to shoot over my shoulder while I was attending to an athlete on the field/court.
Personally (and professionally), once I have the athlete calmed down and stabilized, it wouldn't bother me if I noticed someone snapping a few pics of a "routine injury" from afar. Since I started taking sports pics (just a couple months ago), I've shot a few ATs on the court/mat attending to injuries, but it was to give the AT some pictures of themselves in action lol.
I had one like that a few years ago. One of the first 2 or 3 games of the year, a girl dribbled down the sideline, fell for a reason I can't recall, and the ambulance was called. Some sort of pretty severe ACL/MCL/PCL tear.
For the record, I posted a shot with her dribbling down the court as well as a couple when she was being attended to. No one complained. She was a senior, and her season was over.
It's sad, but they know the risk. I've broken a bunch of bones, but I don't recall ever having an injury like that.