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

https://news.ycombinator.com/newsguidelines.html

That's because, overwhelmingly, cases like this where people are convinced that something seems "totally astroturfed" turn out to simply be people disagreeing with each other. The community is divided on divisive issues like this one. To a first approximation, it really is as simple as that.

Of course there are also various kinds of manipulation, but because of what I said in the previous paragraph, the only legitimate way to address those is to look for evidence—that means something objective, which is not just based on people having opinions that seem obviously wrong or bad (i.e. sufficiently different from one's own).

This phenomenon is extremely well established and you can find many years of past explanation about it here: https://hn.algolia.com/?sort=byDate&dateRange=all&type=comme... .

Edit: incidentally, perceptions like "Every single time there's an article about $topic..." are also hopelessly subject to cognitive bias. HN has had many, many threads about Uber which have been dominated by negative sentiment.