Earlier quoted context omitted.
"You know perfectly well" is a way of accusing another person of being disingenuous and this is a step into personal attack. We don't know what others know—that would require being a mind-reader—and it's against the site guidelines to be aggressive about it. https://news.ycombinator.com/newsguidelines.html
We have a good idea because other people have comment histories and have demonstrated their own linguistic analytical skills on many occasions.
Your comment would have been just fine if it started at the "Many posts are being [etc.]"