You should read the reaction of the Rust community leaders to the quoted article, and you'll see that they share your opinion that something must be done.

At the same time when you have people in the community saying politely and cheeringly that “you'll get over it when you've internalized the rules” what are you supposed to do as a mod? It obviously doesn't infringe the code of conduct even though it seems to have offended the author of the article.

Also, when what the people get pissed of about a community is “they don't want to admit it doesn't work” it's had to say that the toxicity is “people are still experiencing toxicity on the level of other communities that don't have a code of conduct”, by any means…

The goal of a CoC is to make sure nobody gets bullied or harassed, not that nobody will ever get annoyed by other people. You can't make sure you don't have idiots in your community, all you can do is making everyone behaving in a civil manner, which is already hard enough.