That's a good example of the problem. Well, it's not about bots, but the same definitional and logic problems are evident. The story defines "troll farms" as "professionalized groups that work in a coordinated fashion to post provocative content, often propaganda, to social networks". That description is so vague it could describe almost all news outlets and political parties, along with many charities. But, they aren't going to classify CNN, PETA or the White House itself as a "troll farm" although it would be easy to argue otherwise.

Facebook obviously has big problems with internal activists who are trying to convince the company to pursue an ever-spiralling purge against their ideological enemies, and good evidence of that is the unfalsifiable nature of the descriptions of the enemy.