Speaking as a passanger, I feel that he's got off very lightly, on the basis of the facts on the bbc website.
There is a vast difference to being violent and abusive in an aeroplane than in a pub or other public place. On an aeroplane, the victim can't run away, nor can he make the assumption that in a short space of time, the boys in blue will come bursting in through a door, ready to use their truncheons as required. After the assault, the aggressor and victim then have to share the same space for at least a few hours, and the victim will no doubt be wondering if the behaviour will happen again.
One other interesting point - if the flight was between Heathrow and Tokyo, why wasn't Jones handed across to the Japanese police on arrival?
cur