As with all Western Leftism, it is impprtant to understand that most people who identify with any label probably haven't even read the basic canon associated with it and are just going off of vibes. And that online Western Leftists also bring with them an insufferable internet debate bro villification culture where they join affinity groups to crap on everyone else (not jist anarchist affinity groups!).

This is how you get very real irl situations like where a self-described "anarchist" calls everyone that criticizes with him a cop but then physically threatens people if they are in any way disruptive. Or where a self-described "anarchist" constantly delays trivial decisions because they aren't being made "horizontally" enough, i.e. by consensus of every member of the group in 5 hour meetings every day. And why an irl anarchist has to explain the most basic anarchist theory to both of these Kinds of Guy, who are also the most sectarian Kinds of Guy.

So, there is at least one strain of Western "anarchism" that is just selfish people with no interest in theory or history or what anarchism even means but who enjoy the idea of maximizing their own autonomy and aesthetic without thinking about how it impacts others. And these folks will gladly go after anyone they label "authoritarian", which ends up being anything from a major state bureaucracy to literally having a bed time (like quiet hours at night so they don't wake others).

There is also a strain of Western "anarchist" that does begin reading, though not very much and from a selective canon. They do not read in a capacity that produces self-criticism or compares perspectives, but instead treat it more like an in-group romantic mythology of valiant political failure. These "anarchists" often become doomers and declare revolution impossible. They are the most guilty of sectarianism, as every single one of their major "histories" is about telling a false story of how everything was going great until "the Marxists" screwed them over, eliding several important details and basically just promoting the most sectarian people of the past to the exclusion of everyone else. IRL these folks are basically indistinguishable from the know-nothings, they engage in the same antics that force anarchists to correct them because they are bring embarrassing and counterproductive. This is because they are only theoretically anarchist, they spend their political time constructing a utopian view and gaining a false sense of their own correctness and run into irl situations where they actually have no idea what they are doing. Most of these people don't do anything at all irl and along with the know-nothings these are the people who dominate online "anarchist" spaces that are so viscerally, yet ignorantly, sectarian. I think of both of these groups as people that are arrogant, they simply don't read the basics of what would be needed to form their opinions, and their "tendency", if you can call it that, never pushes them out of that ignorany comfort zone. It is unsurprising that it is in such solidarity-free contexts that you get fed-like behavior.

To try and explain why these groups can exist, we should ask why they are not taken over by the sentiments of anarchists that do read and understand and why they are not rapidly redirected to other tendencies. The most important differentiators are (1) whether a person does irl orgsnizing and (2) whether a person reads critically and sufficiently.

Re: irl work, anarchists that do irl organizing work are generally not as interested in sectarian infighting, they are trying to increase the capacity of their projects and will work in coalition to do so. They simply do not think of Kronstadt or whatever when it comes time to raise funds for a mutual aid event. They are busy doing anarchist things, not dedicating their political lives to internet rage. And because they prioritize work over pointless sectarianism, they tend to also moderate their stances due to exposure to good peoplr that are MLs or Maoists etc. IRL anarchists are not free of sectarianism, but it is less unrealistic and dominant. So the online "anarchists" that overreoresent sectarian "tendencies" reflect an atomization, they are people who understand politucs as a form of self-discovery and expression and black team vs. red team, which is to say, a fundamentally bourgeois framing cultivated by who controls the online venues and wider cultural hegemony.

Re: reading, to be honest the Western Left is all guilty of this. MFers need to fuckin read holy shit. The number of people who think they have earned the right to explain things to others despite never reading the material? I swear to God this is most self-described commies and anarchists and socialists. And they often whine about it, too, as if they couldn't possibly take 30 minutes per day out of their internet rage time on their infinte knowledge source device to instead understand the basics of the world-historical project they claim to be forwarding and representing. This is part of the same atomization, though. People in irl orgs often have reading groups and social pressure ensures that some baseline of reading is achieved and this applies to both anarchist and commie formations. Even with that, there is a need to shed liberal ideas around what it takes to have an accurate understanding of something, as Westerners are all taught arrogance and egoism when it comes to politics. Reading properly requires undoing several layers of psychological defenses, of defensiveness itself, of creating spaces where saying, "I don't know" is fine for new members and where the flipside, of people pretending to kniw while providing the worst takes you've ever seen, are overcome by those who develip correct takes and have organized accordingly. Fundamentally, that is also driven by attempting to create good irl organizations. If you spend your time figuring out how to grow and develop your organization, you end up trying to create these spaces and developing each other theoretically. And you also learn that sometimes you need to excise toxic people that are not yet far enough along in their journey to respond to this kind of serious organizing.

I haven't talked much about theoretical differences or historical grievances, or tge First International, etc because I think this largely misses the reality of what Western Leftists, including the majoriry of sectarian "anarchists" are doing. They are more shibboleths for identities and squabbles, stand-ins for a more basic problem of social organization and socialization itself. They are rarely real theoretical disagreements. It's nice when they are, don't discount the value of constructive criticism by comparing to anarchist positions and vice versa, but that is really just plain not what is actually happening 9 times out of 10 that someone online says they love Kropotkin.