I feel like I am repeating myself. Here is the chain of arguments
1) A normal person seeing this article and its upvote count will walk away having a very negative view of LessWrong (reasons in my original reply)
2) Making the valid points of this article is in no way dependent on the negative consequences of 1). You could do the same (in fact, a better job at the same) without offending anyone.
3) LessWrong can be a gateway for people to care about existential risk and AI safety.
4) AI safety is arguably the biggest problem in the world right now and extremely low efforts go into solving it, globally speaking.
5) Due to 4) getting people to care about AI safety is extrmely important. Due to that and 3), harming the reputation of LessWrong is really bad
6) Therefore, this article is awful, harmful, and should be resented by everyone.
A normal person seeing this article and its upvote count will walk away having a very negative view of LessWrong
I feel it very much depends on your idea of a "normal person".
Someone I consider a "normal person" would zone out after the first couple of paragraphs and go do something else. People who are sufficiently abnormal to finish that post (but still someone I'd consider "close to normal") would NOT walk away with a very negative view of LW.
Clearly we have a different idea of what's normal or close-to-normal.
...LessWrong
It's great to make people more aware of bad mental habits and encourage better ones, as many people have done on LessWrong. The way we deal with weak thinking is, however, like how people dealt with depression before the development of effective anti-depressants:
The only "anti-stupidity drugs" we have are nootropics. But the nootropics we have weren't developed as nootropics. Piracetam was, I think, developed to treat seizures. L-DOPA was developed to treat Parkinson's. No one knows who started using ginkgo biloba or what they used it for; it was used to treat asthma 5000 years ago. Adderall derives from drugs used to keep soldiers awake in World War 2.
And none of them are very good against stupidity. AFAIK, to date, not one drug has been developed by understanding and targeting the causes of different types of stupidity. We have the tools to do this--we could, for instance, sequence a lot of peoples' DNA, give them all IQ tests, and do a genome-wide association study, as a start.
We don't research these things because society doesn't want to research them. People don't conceive of stupidity as a disease that can be cured. We need, somehow, to promote thinking of stupidity as a mental illness. As something drug companies could make billions of dollars off of.