Actually, the NCAA rules do have this: "No player...shall...engage in such acts that provoke ill will or are demeaning...to the image of the game." I'm not convinced that acts against a teammate are always excluded from that, although in the OP video I don't see an act that rises to that relatively high bar. But lets say that the player slapped retaliates and the two end up throwing punches until they are separated, and then continue to loudly verbally abuse each other until they are escorted out of the team area - isn't that demeaning to the image of the game?
So is a coach screaming at / berating his players and assistants on the sideline, but we don't get involved with that. A bit more subjectively, multi-color and/or wild haircuts, excessive face hair, hair hanging out under a helmet, exposed tattoos, etc., IMHO, are exceptionally demeaning to the game, but we certainly don't get involved with those, either.
As much as we might want to be, we are neither social police, nor are we the parents of these people (at least I would hope none of us would be 1) working our own children's game, or 2) have a child that behaves so boorishly).
Can't speak for other organizations, but, for UIL football (Texas), if any TASO official observes some similar behavior, and he/she feels compelled to do something about it, by all means, feel free to note the time, and send an incident report to the UIL following the game (and hope that it shows up on video). That is not only the official process, but it is one that everyone with UIL and TASO highly endorse. Do not be reluctant to use this process.
But, otherwise, leave it alone on the field.