My bad, although you were talking comments.
Look at my profile. The number of submitted memes that are missing? All downvoted to oblivion.
They were bunk anyways, just made to hit 1000 so I can meme comment.
All the memes I've seen complaining about getting unfeatured, on the other hand, have been because they were flat out stolen as is, not made on site. Or were offensive.
Also, not aware of any such gangs. Memers like Damaged & Jeff have retreated to their own memes, hardly posting on others anymore, Politics Too was created as a refuge from getting piled on by Alt Righties. But then it went Animal Farm itself.
The only ones that can be looked at as ganged on was Grind & BillyV. But that was independently, en masse, not coordinated, and for obvious reasons. Same with DJFox. He started getting hit by various he annoyed, again, independently.
Speaking of... He and others did openly collude to DV me, and attempted to recruit others for that.
So while it happens, not sure where it's political stances as opposed to personal grudges.