"Please don't post insinuations about astroturfing, shilling, brigading, foreign agents and the like. It degrades discussion and is usually mistaken. If you're worried about abuse, email hn@ycombinator.com and we'll look at the data."

Here's plenty of past explanation about why we have this rule:

https://hn.algolia.com/?sort=byDate&dateRange=all&type=comme...