The flags on hn are extremely powerful, so I don't doubt this. Just a few flags obliterate a post with tons of upvotes. It wouldn't take many people to kill it, and it doesn't require a conspiracy
I will frequently flag posts that are rage bait or where the comments are just the same few people arguing. I haven't flagged this one because I commented in it but it's a very low value post.
It's gossip rage bait to feel the feelings of superiority in the writers community vs VC land. It doesn't dive into any of those things, if it did that could be valuable, it's just reporting events to drive feelings.
Dang said they didn't do it and it's being flagged by users.
Which obviously makes sense of you think about it.