National Film Registry

It hasn't forced the others to be released. I think it's probably because the other films were more influential in and of themselves whereas Return of the Jedi is a great capper on the trilogy, but maybe not as critically regarded for its own merits...? I dunno...people just generally seem to think there's a quality loss after Empire. Which, I think is true. I'd still put Return of the Jedi into the NFR, though.