absolutely, it was wrong.
First of all, this is sports. All these athletes make good money (some much more so than others). And it's good sportmanship to shake hands and congratulate the victors.
In real life (like in a fight, or a war), all bets are off the table. What matters is that you destroy your enemy.
But, in sports, it's a game, it's entertainment. Sure, you should take it seriously, but, once the game ends, you need good sportsmanship. After all, athletes still get to go home to their mansions