HN has ~a decade of history of manipulation in the past and more traffic than ever so naturally it will be targeted more too. If you see anything you think is manipulated this is the person to contact -

https://news.ycombinator.com/user?id=dang

He's got all the data to confirm suspicions and can be reached via hn@ycombinator.com, doesn't matter how many times you're wrong either lol.