While I too have blamed Abrams before for some of the shit that happened in
Lost, he actually had a pretty limited role in that show. The person who really deserves the blame is his frequent collaborator, Damon Lindelof, who was the showrunner. Lindelof doesn't exactly have a great track record when it comes to sci-fi. He produced (but didn't write) the first nu-Trek, and he wrote (in part) the second nu-Trek,
Cowboys and Aliens,
Prometheus,
World War Z, and most recently,
Tomorrowland, providing the wonderful director Brad Bird with his first critical flop. These are all movies in which pretty much everyone agreed that the biggest weakness was the writing. Still,
Lost did have a lot of good things going for it, and more recently, Lindelof has been the showrunner of the critically-acclaimed, rooster-approved
The Leftovers, so maybe his talent is just better suited for television? I'll grant that he at least tries, which is more than I can fucking say for the other two frequent collaborators of Abrams, the shit-shoveling hacks-for-hire Alex Kurtzman and Roberto Orci. Fuck those two, seriously. Their filmography reads like a fucking criminal indictment.
The Island.
The Legend of Zorro. The
Transformers series.
The Amazing Spider-Man 2. And, you guessed it, both nu-Trek movies. Orci in particular is an unpleasant shithead who's
taken to the Internet before to insult people criticizing those films, and it's been
convincingly argued that his nutty conspiratard beliefs may have played a role in how confusing and nonsensical
Into Darkness's plot was. He was briefly tapped to direct the third nu-Trek, too. Just saying, sometimes people blame Abrams for things that are really the fault of his lousy writers.
Anyway, Abrams didn't write either of the nu-Treks, but he did have a hand in writing TFA, so I'd say he's a reasonable choice of person to blame for the oversight. I certainly don't think that they were mandated by Disney to keep the FO vague. What would be the point of that?