You are correct that people judge documentation off of grammar and punctuation. But this is not a rational or logical thing people do. But I can't blame you or others, I mean after all the world believes in religion, myths and other fantasmic spiritual things with no solid evidence as backing. It's normal. I just felt HN was above that. Guess I'm wrong.
>...seems shallow / callous.
Seems that way only because you're not thinking deep enough. Think carefully whether it is rational or logical to judge the works of say Einstein because he had a grammar error or bad handwriting. The two are completely orthogonal and that is the rational perspective.