"Please don't insinuate that someone hasn't read an article. "Did you even read the article? It mentions that" can be shortened to "The article mentions that." "
It's fine to comment without reading/viewing the submission, and I'm sure many of us do :)
Although, I am curious as to why kikoreis doesn't use YouTube?
Sure, but if they explicitly say they haven't read it, then make a wrong assumption about it, surely you can call them out
That lack of a written guideline does not make it okay or a good idea to comment on the article based only on the headline like the GP did. Fine if you're responding to other people on other topics, but positing a straw man argument against your imagination of the article's contents without reading it, the comment will be rightly downvoted.
The guideline you posted is not the inverse, the guideline you posted is suggesting it's best to not make assumptions. Posting about the article content without viewing it is making assumptions.