To view Facebook as "complicit" is probably not the right way to view things. The fact of the matter is that at scale, it's almost impossible to prevent these kind of thing. Facebook is "complicit" in the same way that, say, the W3C is "complicit": by providing the tools.
Could Facebook be doing better or more? Probably. But they are surrounded by malicious actors from all sides, ranging from people who issue coordinated takedown requests like in this story to people who use Facebook to maliciously push "fake news" stories to just banal and boring spammers to outright scams. Balancing this all out and keeping a grip on things at scale is very hard, perhaps even impossible.
Even HN would be vulnerable to these kind of attacks; HN's scale is much smaller than Facebook's but still much too large for anyone to really get a "grip" on. A few years ago one of my stories got flagged[1], and while I'm probably biased I don't think it should be (I probably should have email dang about it, but I didn't post it myself and didn't really want to bother him with it). Was it "coordinated"? Probably not. The end result is the same though: people abuse the "flag" feature to hide stories they would prefer to not be seen. I also know for a fact that some companies will coordinate employees to upvote comments and stories because I worked for a company that did this.
Is HN currently under attack from coordinated flagging? Maybe, maybe not. I would be surprised if it hasn't happened on at least some occasions, and the only reason it doesn't happen more often is that it's small enough to fly under the radar for most of these kind of government agencies.
I think it's important to have a good understanding of the situation as only with a good understanding can you come up with a good solution. "Facebook bad" may or may not be true, but it is not a good understanding of things.
[1]: https://news.ycombinator.com/item?id=26579225