There's this "Tone Argument" Fallacy Fallacy. You can't win an argument by complaining that the other's tone is unpleasant. So that's a valid fallacy, but it only applies to a particular argument in a particular circumstance. Certain people on the Internet then make the illogical jump to the conclusion that they are therefore justified to use whatever tone they care to in any argument. (And lo and behold, they always "win" arguments.)
