I've always been astounded that nobody seems to notice that Facebook continually announces record users, record MAUs and then usually a week or two after their quarterly numbers announces that they have removing millions of fake accounts. Always after they've 'beaten' on those metrics.
Facebook these days, for me, is 90% dealing with fake friend requests from people that are either clones of real profiles, or just complete garbage. It's part of my dislike of their platform, but they're more afraid of bad metrics than genuinely delighting their customer base.
It becomes a negative feedback loop too. We used to spend significantly on Facebook for several businesses I'm involved in, but now that most clicks are garbage/fake, we don't.
I know twitter gets a bunch of hate for not doing more, but realistically they are actually leading the way. I'm impressed with how they're operating more and more.