Today with my friends we have done a ICC run, and, in the groupe there was a people ( a DK) who was very problematic, and insults all the time when we died or when we were to slow to move in the raid.
I don't know if this topic is usefull and if you can do something against toxic peoples but i try.
I have a screen capture of the end when he insulted everyone if needed
Report if it's actually problematic (racism, harassment [bypassing ignore by making several alts], etc.). Otherwise I recommend on getting thicker skin and using game's ignore function.
Somebody calling e.g. a female dog isn't something worth reporting.