I don't think anyone is saying that if you adore Jerome David Salinger and all his works, but you dislike his f & m names and you don't want to name your kid Holden, because let's face it, he's not that cool, or Zachary because it's too Biblical, and Zooey's too girlie for a boy, and you like Zoe for a girl but not that weird version, and Franny's just ugly, noone will pronounce Esmé the way you want to, and Phoebe's too popular, and Stradlater is just weird, Jane's too plain (and I can't remember more), but hey, there's Salinger! Wohoo! You can call him Sal! Her Sally! Yay! That's not a problem for me.
I think it's pretentious when people pick a name to look well read when they aren't. If you like the name Atticus, but don't like the book/haven't read it/think Cary Grant was cute, don't blooming tell me you named your child after Atticus Finch.
Sorry for that. It's late and I'm tired, but the nightfeed is about to happen so I'm still up...
I think it depends on the character/author. Gatsby, for instance, with the upcoming movie I expect to see a bunch of little Gatsby's running around in the near future. I would doubt that the parents have sat down and read the actual book. Though, again, who am I to make that judgment? Name popularity is a relatively mysterious thing. What makes a name likable to one person, doesn't necessarily make it likable for the same reasons to another. One person may like Atticus because of the literary connection, others may like it because it begins with an "A". Why were the character names chosen to begin with? What made Shakespeare choose Romeo and Juliet, what makes any author choose the names they choose to begin with. Like, John for example. Not every man named John was specifically named for the Johns in the bible.
I think literary names can seem pretentious in a downmarket sort of way, just like Paris or Chardonnay or Bentley. If the parent is a legitimate lover of books, or of France/champagne/stupid cars, that's one thing. If, however, they simply want to denote some kind of artificial, affected sensibility, that's pretentious. It's not necessarily an issue of class or education, but authenticity. For instance, a literary baby name on the child of a small-town librarian would not be pretentious; a literary baby name on the child of a WASPy Wall Street Yale grad who's only ever read Donald Trump's autobiography, however, would be pretentious for days.
Maybe I'm wrong on that, but that's what I've concluded thinking on it recently.