Well, you're right in that it's a bit more than just "poor knowledge sharing". But I'd say it's more specific than unintuitive code that requires knowledge sharing, too - it's code that is unintuitive primarily because its main reviewers are blind to the exactly how unintuitive it is, and thus a vicious circle persists. We can see this in the author's recommendation to have such code be reviewed by newcomers as well in order to break the loop.
Well, you're right in that it's a bit more than just "poor knowledge sharing". But I'd say it's more specific than unintuitive code that requires knowledge sharing, too - it's code that is unintuitive primarily because its main reviewers are blind to the exactly how unintuitive it is, and thus a vicious circle persists. We can see this in the author's recommendation to have such code be reviewed by newcomers as well in order to break the loop.