The autism is relevant because it fits a pattern of triggering autistic reflexes and goading an autistic (or otherwise neurodivergent) child into a fight-or-flight response, then punishing them for it while letting the person who did the provoking go free.
This is hitting someone’s knee with a mallet, and punishing them for kicking. It’s shining a light in their eyes and punishing them for blinking.
Just yesterday I was told of a child who had had their hand held down and their fingers bent back until they were in pain, and they were pleading to be let go… until they struggled and freed themself, and struck out as part of that. The child who did the holding down got a detention. The child who was defending themself got suspended for a day, after more than a week on tenterhooks (which was a punishment, for someone with anxiety and a tendency to catastrophic thoughts, worse than the suspension itself, not even counting that they will now spend the rest of their life in school terrified about the consequences of having this on their record). Because they were on suspension, they missed the ceremony where they were made a school year-level captain for being an exemplary student and an example to others for thoughtfulness and kindness.
The lesson is that autistic and neurodivergent kids can be, and are, assaulted for their disability, and will be punished for defending themselves, where their assailants won’t be punished as much or at all.
That this guy is facing consequences is the exception, and, as PurpleFlower said, he clearly expected to face no repercussions at all.