What caused Guram Tushishvili to snap?

There's fake news going around in social media that the reason Guram Tushishvili got angry at Teddy Riner after he was thrown for ippon in their semifinal match was that Riner pressed on his neck or applied some kind of choke with his bare hands after the throw was done.

If you watch the slow motion replay of the throw, you can see very clearly that no such thing happened. Riner still had his hand on Tushishvili and did not press on his neck or apply any kind of choking action.

So what made Tushishvili snap? Some clues can be found in a still picture of Riner just moments after the throw as well as Tushishvili's gesture after they bowed and shook hands.

Riner raised both his fists in the air, jubilant that he had beaten one of his toughest rivals. That, apparently, was the incident that triggered Tushishvili. You can see after Riner shook his hands, Tushishvili raised his fists in the air exactly like Riner did and shook his head in disapproval, as if saying to Riner: "You should not have gloated like that".

Of course, Tushishvili is wrong. First of all, Riner was just expressing joy at winning a tough match. He was not mocking Tushishvili. If he did, the referee would have given him hansoku-make (that has happened before). Secondly, whatever the provocation may be, what Tushishvili did was totally uncalled for and he rightly deserved the hansoku-make he was given, for going against the spirit of judo.