The lowest value contributions on HN are inevitably those that use a headline to air personal grievances vaguely related to the subject of the post (“Apple releases new cure for diabetes”, top comment: “Let me tell you why I hate the touchbar.”) the second lowest are those that clearly read the headline and ran with it, without reading the content that utterly contradicts what they imagine the article would contain.
Not having read the article / not discussing anything in the darn article should absolutely be grounds for criticism.
Drives me mad. Any Hacker News discussion has an extremely strong push towards the same couple dozen topics that anyone can relate to, and commenters who drag the conversation in that direction for no good reason are doing the thread a disservice.
1) Please read the article before you comment.
2) If you haven't read the article, please refrain from commenting.
It wouldn't accomplish much, but it will at least prioritize engagement over politeness, as the current rule does. And yes, both of those are the same thing but I feel it's worth mentioning twice.
Nothing in the rules discourages downvoting people who didn't read.
Writing an article about bad habits in cyberspace where the title of your piece vaguely calls to mind some guideline in some forum and appears to contradict it is not somehow a violation of that guideline.
As someone with eyesight issues and a demographic outlier for HN who, thus, sees life different from most people here, it's sort of common for people to think I didn't read something when I did, I just missed a detail or I did, I just have a different education and life experience and see something different in it.
And that's one of the reasons you shouldn't say that to someone directly. You are assuming something ugly, basically.
But talking about how reading the article before expressing your opinion is a best practice is unrelated to that detail of etiquette.