Ad hominem is, I think, the most prevalent and harmful fallacy on the whole internet and society at large. In fact, not to make everything about the Reddit situation, but we saw u/spez recently employ it by evading questions and trying to impugn developers.

And of course, in the political space, we see it all the time to try and dismiss any pro-worker arguments. In the United States, labeling someone as a socialist has been used as a Q.E.D. in itself for decades. I hope that’s changing.