This is exactly why have 19's been going downhill for over half a decade. People seem to a very difficult time keeping their electronic egos in check over a single loss in a video game.
People need to come to the realization when you play a game that keeps a score there will a team that wins and there will be team that loses.
Mature, gracious winners don't gloat. They let their win speak for itself.
Losers don't make excuses, they learn from their errors. And hopefully comeback stronger.
What we witness over and over is winners gloating and losers making up excuse after excuse to the point that people don't even want to play because they are afraid they will be on the negative end of the bullying.
GMs should wrangle these misfits in if we want the 19's to prosper again.