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?
I am referencing your knee-jerk "both sides" rhetoric that pops up instead of even acknowledging the point I've made.
The ones I have already corrected you on, such as the Black Army "overperforming". It performed as well as any guerilla group under circumstances favorable to guerillas of the time, i.e. with sufficient support from the peasantry. Given how dramatically it ultimately failed, and its many faults, this is really a romantic characterization that doesn't do justice to anyone involved. Did they really overperform? How well "should" they have performed? Such ahistorical romantic characterizations, along with backstabbing narratives, are the main theme of "anti-Marxist" mythologies among self-proclaimed Western anarchists.