I don’t think witch-hunting at any scale should be okay on online forums. Please don’t. Maybe respond without feeling the need to visit someone’s profile or history?
What if someone has a hidden agenda and in isolation their arguments seem sound, but when you zoom out you see the agenda and understand that the arguments are biased and manipulative and actually counterproductive?
Because in many cases no "troll" has been found at all; and discouraging people from witch-hunting leads to a more positive environment that's conducive to interesting conversations. Often the witch hunter is just salty about something someone said. For instance, thomasanders0n is evidently a big fan of Paul Graham's writings. I left my impression of their article, which was short and to the point; I personally think the article is so bad that doesn't merit a lengthy teardown. But because I feel differently, my response has been interpreted as bitter and jaded. Shrug.
