OP, the link is to lemmygrad.ml but you keep citing lemmy.ml in this thread; are you mixing up the 2 without realizing it or do you intend to mean both?
I haven't seen much of anything on lemmy.ml that reaches grad.ml's level of what you describe. Then again, I stick mostly to somewhat-niche interest subreddits that receive a decent amount of participation from other federated servers.
In my experience even hexbear users are surprisingly (for the internet) good and decent to others, as long as you can avoid provoking their "the capitalist US empire is the current hegemony that's killing the planet and ourselves, and we don't punch down, therefore our vitriol is a uni-directional torrent" mode of operation that others in this thread have mentioned.
Obviously, the classical "cult" approach resembles that as well (love-bomb anyone not explicitly an enemy, close ranks against any potential discrediting of the movement). In my books most of them are ordinary people, from whom (legitimate) despair of the current state of the world has leeched all desire for compromise.
I don't have a less patronizing way of saying it, but they remind me of someone who, after years of abuse by their partner, finally snaps and gravely injures said partner. In some sense, it's on the rest of us to not have intervened beforehand, and at the same time their lashing out really doesn't help things.
Oh, and this probably reads as hippy anar-kiddy logic to them, which is part of why I personally stay away from most of their politics-related communities.