That whole "mindkiller" thing really rubs some people the wrong way; for such a person, politics are so bound up with ideals of rationality that staying away from them looks not just ignorant but willfully and maliciously so. (Compare the "reality-based community" on the left, or Eric Raymond's "anti-idiotarianism" on the right. Not that we're entirely innocent of this sort of thinking ourselves.) Combine that with the absurdity heuristic and our bad habit of parochialism in some areas, and you've got most of the ingredients for a hatchet job.
I think it's more that the things Arthur is responding to are, in fact, very racist.
Reading just his comments (I control-F'd 'arthur chu' on the second linked post), it seems that he clearly understands the dynamics of racial privilege, the concept of minstrelsy, and how those relate to contemporary social justice struggles in macro and micro (American belly dancers), but seemingly none of the people he is communicating with do.
This is a quote I can identify highly with:
That post [the one debunking false rape statistics] is exactly my problem with Scott. He seems to honestly think that it’s a worthwhile use of his time, energy and mental effort to download evil people’s evil worldviews into his mind and try to analytically debate them with statistics and cost-benefit analyses.
He gets mad at people whom he detachedly intellectually agrees with but who are willing to back up their beliefs with war and fire rather than pussyfooting around with debate-team nonsense.
There is a saying in the anarchist community, dating back to the Spanish Civil War: No Parasan. It means "No platform" and maps to "no platform for fascists." It's why groups like the "national anarchists" and other third-positionist fascist groups get kicked out (in a literal sense, their propaganda destroyed and their bodies thrown out) of anarchist events.
No Parasan actually has a very compelling social and cognitive explanation: The more you detachedly argue with fascists, the more normal and accepted their politics become. The BNP is a great example of this. And as it becomes viewed as an acceptable alternative, fascism gains support (which is why the BNP could succeed as a novel fascist organization in the UK).
When discussing existing oppressive social structures such as patriarchy, white supremacy, colonialism, and capitalism, attempting to dispassionately argue causes this phenomenon at best, and at worst actively silences the people victimized by such structures.
Scott Alexander is not an ally to rape survivors because he has normalized their oppression. He has tried to debate with a monster instead of annihilating it.
I think the real reason why Arthur Chu is so pissed off at LW is because LW has all the mental tools available to recognize that discussing certain things can be harmful when the topic is something rich white men care about: typically AI risk. They get that you only tell wizards strong enough of a particular spell, but then disregard it. In a word, Less Wrong is blind to its privilege.
This isn't surprising, because rich white men in general are blind to their privilege, and even relatively well-off women or people of color can be blind to their oppression if they're able to buy their way out of it, but that doesn't mean those concepts don't exist.
Less Wrong is right that politics is the mind killer. Less Wrong just had it's mind killed early on when it decided it would only ever accept the politics of the status quo. If Less Wrong had been around in the 1820's it would have supported slavery. If it was around in the 1940's it would have supported Jim Crow. The fact that Less Wrong can't collectively see this is infuriating to some people, including to an extent myself.
I'm not personally about to say Less Wrong is a religion or a robot cult or whatever, it has hilarious views sometimes that are pretty normal for any internet community, but as someone who identifies problems with the contemporary political order and wants to change them, Less Wrong cannot be my comrade in this fight.
As an aside, unrelated from anything I've said previously, anyone should agree that LW habitually loses even though it should win. CFAR is a good attempt and the most winning thing I think I've seen out of Less Wrong, but it's far from that I feel LW could produce. Maybe the people who could produce those things aren't on less wrong because they're producing them, but if they knew so much of their own success came from knowing basic rationality, why wouldn't they recruit here?
Edit: As another aside:
In other words, if a fight is important to you, fight nasty. If that means lying, lie. If that means insults, insult. If that means silencing people, silence.
Holy shit yes! If you have anything to protect use all of your available strength to protect it! Shut up and multiply, think for at least five minutes about the problem, apply every ounce of your technique and then win. I truly and sincerely hope that every last person working for MIRI would kill and die to bring about friendly AI. I hope that if I had the choice of sacrificing myself so that all of humanity could live forever I would take it. If a fight is so important that you must win it, you must win it. You can win by the long sword, or you can win by the short sword (to quote Musashi) but you must win.
Any rationalist should see this trivially. It is a failure of Scott's that he hasn't, though I suppose he could be appealing publicly to the a widely-held principle in order to win this particular debate.
In other words, if a fight is important to you, fight nasty. If that means lying, lie. If that means insults, insult. If that means silencing people, silence.
Holy shit yes! If you have anything to protect use all of your available strength to protect it! Shut up and multiply, think for at least five minutes about the problem, apply every ounce of your technique and then win.
Whatever you happened to believe, the winningest answer would be "No, never lie". Because now that you've claimed your political position is likely to be based on lies,...
The public debate is rife with fallacies, half-lies, evasions of counter-arguments, etc. Many of these are easy to spot for a careful and intelligent reader/viewer - particularly one who is acquainted with the most common logical fallacies and cognitive biases. However, most people arguably often fail to spot them (if they didn't, then these fallacies and half-lies wouldn't be as effective as they are). Blatant lies are often (but not always) recognized as such, but these more subtle forms of argumentative cheating (which I shall use as a catch-all phrase from now on) usually aren't (which is why they are more frequent).
The fact that these forms of argumentative cheating are a) very common and b) usually easy to point out suggests that impartial referees who painstakingly pointed out these errors could do a tremendous amount of good for the standards of the public debate. What I am envisioning is a website like factcheck.org but which would not focus primarily on fact-checking (since, like I said, most politicians are already wary of getting caught out with false statements of fact) but rather on subtler forms of argumentative cheating.
Ideally, the site would go through election debates, influential opinion pieces, etc, more or less line by line, pointing out fallacies, biases, evasions, etc. For the reader who wouldn't want to read all this detailed criticism, the site would also give an overall rating of the level of argumentative cheating (say from 0 to 10) in a particular article, televised debate, etc. Politicians and others could also be given an overall cheating rating, which would be a function of their cheating ratings in individual articles and debates. Like any rating system, this system would serve both to give citizens reliable information of which arguments, which articles, and which people, are to be trusted, and to force politicians and other public figures to argue in a more honest fashion. In other words, it would have both have an information-disseminating function and a socializing function.
How would such a website be set up? An obvious suggestion is to run it as a wiki, where anyone could contribute. Of course, this wiki would have to be very heavily moderated - probably more so than Wikipedia - since people are bound to disagree on whether controversial figures' arguments really are fallacious or not. Presumably you will be forced to banish trolls and political activists on a grand scale, but hopefully this wouldn't be an unsurmountable problem.
I'm thinking that the website should be strongly devoted to neutrality or objectivity, as is Wikipedia. To further this end, it is probably better to give the arguer under evaluation the benefit of the doubt in borderline cases. This would be a way of avoiding endless edit wars and ensure objectivity. Also, it's a way of making the contributors to the site concencrate their efforts on the more outrageous cases of cheating (which there are many of in most political debates and articles, in my view).
The hope is that a website like this would make the public debate transparent to an unprecedented degree. Argumentative cheaters thrive because their arguments aren't properly scrutinized. If light is shone on the public debate, it will become clear who cheats and who doesn't, which will give people strong incentives not to cheat. If people respected the site's neutrality, its objectivity and its integrity, and read what it said, it would in effect become impossible for politicians and others to bullshit the way they do today. This could mark the beginning of the realization of an old dream of philosophers: The End of Bullshit at the hands of systematic criticism. Important names in this venerable tradition include David Hume, Rudolf Carnap and the other logical positivists, and not the least, the guy standing statue outside my room, the "critical rationalist" (an apt name for this enterprise) Karl Popper.
Even though politics is an area where bullshit is perhaps especially common, and one where it does an exceptional degree of harm (e.g. vicious political movements such as Nazism are usually steeped in bullshit) it is also common and harmful in many other areas, such as science, religion, advertising. Ideally critical rationalists should go after bullshit in all areas (as far as possible). My hunch is, though, that it would be a good idea to start off with politics, since it's an area that gets lots of attention and where well-written criticism could have an immediate impact.