I don't follow the reasoning.
Were the boot on the other foot, and remarks were reported, I am sure they would be considered seriously. I am aware of a number of prosecutions for anti English remarks in my home county.
For what it is worth, I think it is generally ridiculous to hold people to account for their behaviour whilst drunk. People are being added to the sex offenders register for mooning for goodness sake!
Where the behaviour is criminal, and has a victim who can be shown to have suffered, that is a different matter.
It is in the nature of sporting rivalries for the misfortune of opposing teams to be exploited.
I am certain the daft boy would not have made that initial remark if it was clear the footballer had actually died.
It also seems likely to me, that he then made any further remarks in a reactionary way, as he was offended by being labelled as a racist, and wished to wind up those taking such a cheap shot.
His mistake was to react in that way, and then to 'publish' his remarks.
Were I accused of being violent, it would probably not be best to hit the accuser in ironic counterpoint to what I would wish to assert was the truth. I may be a serial killer, but I am not violent.
He has owned up, shown remorse and should be allowed to get on with his life. The idea he might be ousted from his university is truly disgusting, and I hope he can challenge that legally.
This is not really the best use of prison, I only hope he is not forced to mix with real criminals.