You can have click/troll farms with real humans (going thru VPNs, BOT networks, etc). Even "normal" people who are "paid" (for instance gacha game campaign offering in-game resources for free, that in exchange of a good "review", yes they can link the review with the right account for resource "reward", and it seems it can go down to social networks).
https://news.ycombinator.com/item?id=44785636