i.e. The real problem with Facebook and the News is that facebook is fucking blatantly spreading propaganda by misrepresenting consensus and then lying about it.
I'm not saying they are dumb. I'm saying not that many would stop and seriously think if 'trending' news section on FB was possibly being used for spreading propaganda.
I don't think people necessarily thought that it was a purely automatic algorithmic creation (although I wouldn't be surprised if that was the case -- remember that most people are not nearly as tech-savvy as the HN crowd in knowing what is or isn't likely to be the result of "pure algorithms"). But the fact that it's called "trending" inherently implies that it's a representative snapshot of what the current attention ecosystem is -- that it's a passive record into what "is trending." By manually inserting or removing things from the "trending" list, that creates a false impression that certain things are or aren't popular.
I would say it's good they do that. Just like dang & co diligently try to control what gets to frontpage and what doesn't (specifically, banning certain outlets known to be bad/unreliable and trying to slow down hastily-thunk grab-your-pitchfork movements in favor of rationally-minded and considered stories).
If you don't do this, Trump happens. Trump is a product of a capitalistic-media which kept providing an easy diet of shit. If facebook is preventing brietbart stories from reaching the top, more power to facebook.