Edit for clarity: I'm not asking why the Tankie/Anarchist grudge exist. I'm curious about what information sources - mentors, friends, books, TV, cultural osmosis, conveys that information to people. Where do individuals encounter this information and how does it become important to them. It's an anthropology question about a contemporary culture rather than a question about the history of leftism.
I've been thinking about this a bit lately. Newly minted Anarchists have to learn to hate Lenin and Stalin and whoever else they have a grudge against. They have to encounter some materials or teacher who teaches them "Yeah these guys, you have to hate these guys and it has to be super-personal like they kicked your dog. You have to be extremely angry about it and treat anyone who doesn't disavow them as though they're literally going to kill you."
Like there's some process of enculturation there, of being brought in to the culture of anarchism, and there's a process where anarchists learn this thing that all (most?) anarchists know and agree on.
Idk, just anthropology brain anthropologying. Cause like if someone or something didn't teach you this why would you care so much?
An interesting connection that I've observed over and over again to the point that it's practically a law in my head, is how many of these newly minted anticommunist "anarchists" also end up being anti-black or more accurately anti-black radical politics, the same phenomenon emerges subtly among many academic western Marxians and more obviously with the whole maga"communist" conservative subculture
Historically, anti-communism and anti-blackness have been inseparable and the anxiety is obvious, westerners fear communism will lead to minorities escaping their subordinate positions and inflicting some nebulous horror upon them, this anxiety is so baked into American consciousness that you had Trump accuse Kamala Harris (neoliberal par excellence) of being a communist, anyone with sense understood that as being an expression of both anticommunism and more prominently anti-blackness
My theory (which is largely lifted from Professor Gerald Horn) is that anti-communism in the west is directly proportional with anti-blackness and explains the savage irrational anti-left hatred that you observe among so many newly minted so-called radicals, the state and it's various intelligence orgs supply the mental and intellectual architecture of anticommunism while anti-blackness supplies the emotional fuel that sustains that state effort