Users flagged it. Moderators never touched it or even saw it. Probably users flagged it because a closely related story was on the front page all day: https://news.ycombinator.com/item?id=21310867. Follow-up or copycat submissions aren't exactly dupes, but people read HN for topics they haven't seen recently, and HN basically never wants two front page submissions about the same thing.
Your comment breaks the site guidelines against insinuating astroturfing without evidence. A story getting flagged is evidence of nothing other than that users flagged the story. Admins conspiring to suppress it? that is pure imagination, and it's pretty nasty to imagine something about someone and then accuse them of being paid to do evil. The guidelines exist to prevent HN from degenerating that way, so please read and follow them when posting here from now on: https://news.ycombinator.com/newsguidelines.html.
Your comment breaks the site guidelines against insinuating astroturfing without evidence. A story getting flagged is evidence of nothing other than that users flagged the story. Admins conspiring to suppress it? that is pure imagination, and it's pretty nasty to imagine something about someone and then accuse them of being paid to do evil. The guidelines exist to prevent HN from degenerating that way, so please read and follow them when posting here from now on: https://news.ycombinator.com/newsguidelines.html.