In general, I don't type in game period, so this isn't a "what can I get away with" thread. This is more based on what I've seen others type.
I've sorta adopted this mentality that if some one is trash talking in all chat during the game that I'll let it go until it goes to far. Like saying "nice flash" when someone fails flash is fine but "nice flash %%%%%%" I will report. Personally I don't think trash talking should be allowed but Riot allows it so whatever, I had to draw my line in the sand somewhere so this is what I choose.
Now, I had a game where apparently people were talking in all chat. I have all chat turned off so I never see it but my teammates were discussing what the enemy was saying. Team made some questionable plays and we lose. Fine, whatever. Get into the end game lobby and the enemy team is all "you all suck", "losers", "trash", "go to sleep", "uninstall", "0/6 report for inting", etc. None of this is insanely toxic mind you, but it's being a bad sport. They already won so now they are just stroking their egos.
To me, any trash talking after the victory/defeat screen is toxic. Now it's no longer a mental game, it's kicking another while they are down. Apparently these people don't see it that way so I wanted to know what the you think. Again, I don't like trash talking and don't do it, but since Riot thinks it's ok, at what point does it go from trash talking to unsportmanlike?