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?
Disclaimer: This does not apply to all or even most anarchists, and may apply to, like, 5, because it's my personal impression from a handful of miserable encounters.
As a USSR-specific example, since that's what you're asking for, there are some anarchists who are evidently taught that Nestor Makhno was a brave resistance fighter rather than a negligent armer of pogroms and leader of aremoved gang (though probably not personal participant, he just let his men do it). Having this image of a champion of freedom and then hearing how he was militarily crushed by the Bolsheviks, naturally they will resent the USSR as counter-revolutionary. Spain is obviously another example, where the SU's role gets contorted from "didn't help the anarchists as much as it could have" to "personally killed anarchists in parallel to the Francoists killing anarchists"
Edit: Down in the thread there's some direct evidence of the romantic tragedy of Makhno being played out yet again.
I don't think that's most of them, but I think a lot of them have these kinds of stories in mind that lead them to deciding the tankies are evil. Honestly with new anarchists who do this shit, it comes off to me as a way to become a political minority, to be involved in a grand historical struggle against the "statists" who always kill anarchists like you (now that you've become and anarchist). Like, in liberal society and not incorrectly, there's a solemnity with which Jewish identities are treated because, in large part, of their ancestral connection to the Holocaust. I have talked to some anarchists that really come across as wanting to opt in to having ancestral oppression like that even if they're as white as untrod snow, and this is a way to do it. I have seriously seen some unironically talk about how Stalin killed "us" as though stanning Makhno or whoever retroactively makes them actually part of that group.
Reread the disclaimer.
HELP, I'm stuck in a loop and I can't stop re-reading this comment.
I was never good at writing code