Well the hard thing about astroturfing is that only the people running the platform have the hard data to prove it beyond any reasonable doubt.

But I don't think we need 99.99% confidence -- isn't even acknowledged that 30% of twitter is bots or something? I think it's safe to conclude there's astroturfing on any significant political issue.

Also as far as documented cases, there were documented cases of astroturfing around fracking [1], or pesticides [2]

1. https://journals.sagepub.com/doi/10.1177/2057047320969435 2. https://www.corywatson.com/blog/monsanto-downplay-roundup-ri...

An ex friend of mine was once involved in some thing where they got paid to astroturf for Monsanto. Despite living in the city, they suddenly developed deeply informed opinions about glyphosate and how important it is for agriculture, and they would share these opinions aggressively in online discussions along with pro-Monsanto articles. It was disturbing to watch because the behavior was completely uncharacteristic (and seemingly in conflict with their core beliefs). One day they quit doing it just as suddenly.

This was before the heyday of influencer culture, so I can only imagine how sophisticated things are nowadays. It’s not always bots.

I recommend the book Trust Me, I’m Lying for a deep but somewhat dated look at the online influence industry.