> We have banned people in a few cases for serious $BigCo astroturfing but there's always a grey area in the Venn diagram around "PR operation" and "overzealous fan". You can't tell those apart without a smoking gun and those are hard to come by.

I can attest to this: at one of my old companies a post related to us ended up getting removed, just because so many of our engineers (entirely independently of the company) voted or commented on it. After that there was a very strict instruction from the company _not_ to engage with any posts about us...