As of right now, yes it is ruining the game quite a bit, and i there are some people who argue that tf2 is a for fun, silly game, and others want to play the game competitively. (though unrelated) look at SSB, i would say that is a silly game, but people still try to play it competitively. The thing is people would like to have a good normal game without any griefing, and yes "just kill them they will start fighting again" would probably work, but why put the effort of starting a game that has already started. people with these taunts should just stick to a more flexible server without an objective.