I agree, TheGoldenKey. Altogether, his “look” and description remind me of Peter Pan, too.
How old was Peter in the story? A young boy, right? Since we know he can traverse between Neverland and our world, he could have been in our world when the curse hit. Maybe that prevented him from going back. That means he could have aged +28 years, which could explain the specific age the casting call was for. (They usually say 20-30s or 30-40s. But this was specific.)
Plus, Peter Pan is supposed to be a favorite fairy tale of the writers, correct? And we know that casting for “Barrett” was for a major recurring character. It fits, I think. Eager to hear other theories!