Ppl crashing when they're about to die to evade losing or opponent gain a win

I've never had this type of problem, probably because I can never really work my way up to a very high league rank, so stakes are a lot lower.

But I agree, it would be annoying. I usually concede when I know I lose, unlike those players who try to stall as much as they can by not pressing the end turn button, and that's already time consuming.