That said, I've never come upon a study that showed significant gains due to targeting, rather to the contrary. – So, after a decade, I'm still waiting for any proof in favor of targeting. (The suspicion must be still that targeting is rather a lazy alternative to media analysis and its perceived advantage is rather rooted in minimising efforts than in effectiveness.)
Regarding "Facebook has created the most sophisticated ad targeting engine", this is a rather biased proposition. It has enforced Facebook as a broker, made advertising cheap, while less effective, and has driven ad revenues for content providers downhill. (Google is to blame, as well.)