Coasted on three movies for half a century but his time as an icon is over now.
He's going to be all but forgotten soon. I don't see James Dean posters or other memorabilia in the shops anymore since maybe the 1990s. No new Dean biopics have been made in a long, long, time. His fellow '50s icons, Marilyn Monroe and Elvis Presley are still very relevant to pop culture, but not this guy.
I would bet the majority of people under 50 have no idea who James Dean was. If young audiences saw his hammy acting in "Rebel Without a Cause" they would just think of Tommy Wiseau imitating Dean when he quotes "YOU'RE TEARING ME APART!" in The Room.