The last thing they want to do is remind people of the worst the franchise has to offer, rather. I don't think Star Wars has lost its appeal. Cultural relevance, perhaps, but that's up to JJ et al to reignite. I think they'll probably do rather well, too. Disney just wants to keep people focused on the future rather than the past. EDIT: A very particular part of the past, rather. EDIT EDIT: Right... relative decline of the prequels, not of the franchise as a whole. The poor box office reflects the poor film (people know what they're getting in a 3D re-release), not a franchise that's lost it's appeal.