I think that sounds a bit far fetched for these forums.
There are ofc those that buy likes, ratings, reviews but generally speaking that is more of a start up thing. Most of the systems in place on most social media etc require a certain level of engagement before they qualify.
People frequently like to call others shills and they have no real concept of what one is. The same as the term whale is generally misused on the forums too.
As for you fake forum comments if you read the article it states that is a problem mainly in China. You could have linked the article despite your paranoia, simply type/paste it in, highlight and use the </> button. Or you need to be a more active member of the forums and you gain trust levels where you can post links. You can read about trust levels in the FAQ pinned at the top of this forum.
How a link looks using the method I described:-
https://www.bbc.co.uk/news/technology-15869683
However with trust levels you can post them like this:-