There's a problem here that people don't necessarily consider. Ignore motives for a bit. Lets say that large groups of people really, really wanted to spread positive, constructive messages on social media. Perhaps about how important it is to read and exercise and not to consume passive content. Or how kind it is to put group differences aside and focus on the things we have in common. Etc.

I'd argue that it just wouldn't work. Outrage is what's "engaging" and it is engagement which actually forces these things to go viral and spread. You are therefor limited in what sort of information you can spread on social media, at least in the virality sense. You could not, for instance, use social media to "trick" millions of people into practicing calculus every day. And you could not use social media to coerce people into spending hours meditating.

It's of course not that you could never house this content on social media, but instead that this content could never be viral, never make a strong, immediate emotional impression in the eyes of the viewer. Practicing calculus or meditation is much, much more than a strong, quick, (and I'd argue) innate emotional reaction to bare stimulus. It requires focus and participation.

So it's not just that there are these little evil troll farms sowing discord around the world. Rather, outrage, and particularly outage about social or tribal topics will always float to the top in any sort of system (algorithmic or not) that preferences engagement. There will always be at least outrage in the general population of posters (whether "natural" or else astroturfed) who are putting out outrage content, and this content will always be treated preferentially in any system that filters for outrage content. It's quite hard to avoid. You actually see this on the "boring" 4Chan boards. There is no algorithm in the modern sense of the word (although of course there is something like an algorithm in the literal sense of the word) and on these boring boards you just cannot get much much traction when starting a thread that is not a "troll" thread. A normal, informative thread gets fewer replies, and so it falls off the front page, and then no one sees, and so it gets even fewer replies.

In other words, these systems will always privilege outrage bait, even if they had real incentives to attempt to avoid it. There are only certain topics that get people fired up in a quick, immediate, emotional sort of way -- and the communication systems we've built and have become addicted to will only preference that sort of communication. Identifying these troll farms matters, but why would a crappy little troll farm from far away be able to to write content that captivates you. If they wrote a book, you wouldn't read it. If you directed a TV series, you wouldn't watch it. But one dumb little caption on an image about how a person from the wrong group has trespassed against you and it sticks in your mind forever. People need to think about why that is.