In my opinion it's related to the growth of identity politics and the 'calling out culture' around that, it's related to some people sometimes being quite damaged and a bit unstable, the collapse of collective structures and growth of individual/small projects, and it's obviously related to the internet in how easy it is for people to say something stupid that exist forever and get picked up on, and how easy it is for people to make accusations, misinterpret something, or just be plain disruptive. Not to mention the tendency for some cartoon anarchists to use slagging off of some things purely as an ideological and egotistical booster to their own identity and position as the only true radicals.
In mine the incidence of people jumping to conclusions, why they do so, how they do so, who they do it to and what the impact might be on any given topic is much, much more complicated (and specific) than the above suggests. And tbh, in itself I'd say blaming "idpol" (which imo is the laziest descriptor to have been popularised on the left in recent memory and is at least as poisonous to clear debate as the various cultures, individuals and fashions it aims to criticise) or "cartoon anarchists" (ditto - I mean fine tell off people for talking bollocks, but acting like armchair anarchism and a censorious attitude/egomania/refusal to listen are one and the same is just
silly - ) is also in the category of "totally bloody unhelpful."
Edit: Just to expand a bit, there was what I'd consider a fairly definitive moment related to "callout culture" and such the other week with
Contrapoints. I'd pick her as probably one of the most important voices about trans issues among the under-30s today, certainly on the radicalish left. She's considered, kind, courteous and open about her politics and often interrogates her own position on stuff.
The other week, she made a comment on Twitter about feeling uncomfortable in spaces where pronouns are announced ("hi I'm Rob Ray, he/him" etc) because she wanted to feel like she could pass (as female) without having to say anything (I paraphrase). The response from nonbinary people on Twitter was huge, thousands of people were posting to her in a range of different ways, from calm consideration of the point all they way up to screaming fury. Which isn't "callout culture" inasmuch as we're not talking about a small number of people deciding to cancel a mate, we're talking about people feeling moved to give their opinion on a matter of interest. Thing is, everything @ her was showing up on her timeline.
Thousands of posts. And regardless of the actual overall tone of the conversation, what it of course comes across as is a tsunami of screaming about you having done something wrong. This caused her to leave Twitter, which actively deprived trans people of an influential voice.
Now the reasons for that tsunami are just unfathomably complex, though you could probably extract key reasoning and critique if you delved into the sum of the posts. The screamy ones could be for practically
any reason, from a bad day to a bad high to a mental break to a poisonous inward turn among a group of friends to just a really headbangy attitude. And there's fuck all we can do about it, because we're not talking about a few rum uns who can be turfed out of the movement, or a bad trend we can reverse, we're talking about globally-constructed masses of people all posting from a million different perspectives and from as many different interlocking community bases, who often have radically different cultural standpoints (eg. US hyper-individualism vs anywhere else). It's a fucking mess, and it's not going away, but it's not particular to the left, to young people, to old people, or to whatever "idpol" is supposed to mean.
This, incidentally, may well be a phenomenon worth interrogating in terms of how different generations are reacting to the various arguments anarchism is having with itself right now. For the younger generation, most of them have grown up with the mute/ban button as the primary means of controlling what would otherwise be an overwhelming whirlwind of bonkers behaviour. Controlling inputs isn't just a matter of whether open speech is needed to develop your politics, it's the only way to filter out what you consider to be worth listening to. The problems that builds are many (political bubbles, intolerance of difference etc) but it's not the weak-minded or cosseted approach that is sometimes projected and a real engagement with this phenomenon actually requires quite a lot of constructive thought, rather than just moaning about teh yoof and their banning and idpols.
Final edit: Having written all this, I apologise for the diversion! I guess it should have been in the identity politics thread, but I really don't like that thread as it basically just feels like a circlejerk". 
