At a certain point school is a grade competition for students and has very little to do with learning. I can't prove this but I suspect there is plenty of cheat

At a certain point school is a grade competition for students and has very little to do with learning. I can't prove this but I suspect there is plenty of cheating at the upper ends of the grade spectrum. Kids know that cheating will not help them but they are competing for grades so it does not matter. Penalizing those at the upper levels of grades would do nothing since they would make enough noise that they would get their way. Also, getting high scores is rarely a problem, if at all. Very few student suffer from that problem. It's so small that it does not need a fix.