I bet people would still want to watch the movie, even if they found out all that would happen over the years. It would be hard to comprehend at that stage, not knowing anything about Star Wars yet. I bet they'd be even more curious, possibly.
That's true George would probably already have gone back and changed the films. Seems like the kind of thing he'd do. He'd probably think, "Wow, I can actually make my 'original vision', my original vision! Let's do it!" It could also be a funny take for a movie tho, I think.