Not really that surprising when you really look at Hollywood as a whole...happens all the time. The George Clooney/Denzel/Will Smith thing is rare (TV actors making it big in movies), a lot of times, television actors and actresses often find it hard to break out into film.
Look at the rest of the Lost cast. Matthew Fox (Jack) shows up here and there, but he's certainly not had a huge career or anything. Evangeline Lilly (Kate) has hardly worked (Although, judging from interviews and the like, I get the sense that she is partially held back by her own choice, she doesn't seem to want it). Terry Oquinn (Locke) is doing TV. Michael Emerson (Ben) was doing TV last I saw. Claire, The Hobbit, Michael, Juliet, the list goes on.
@ Walt barely even having a career now.
It may just be that he's not a particularly good actor....Sawyer was for the most part, fukking awesome, but the role itself didn't necessarily stretch him that much. He could have just been the perfect man for the perfect part, and now, out in Hollyweird where every role doesn't require southern accent and swag, he's having trouble landing parts.
I also happen to know that he, Jin, and maybe a few others (Hurley I think), ended up staying in Hawaii. Maybe he's not there all the time, but I know he ended up like, owning a business and settled down (While still wanting to act of course, but that probably hurts him not being in LA all the time).
