GL kinda hinted that himself, henceforth my sig.Effects were really only a small part of the 'Star Wars' phenomena of 1977, though - even with the fanfare they quite rightly received. But without the interesting story and, especially, the world building, it wouldn't have attracted as much of a loyal following that it did.
That was a rare thing. Before 'Star Wars' you had disco sci-fi, like 'Logan's Run' or dystopian future shock type movies, like 'A Boy and his Dog' or 'Silent Running'. All perfectly fine films. But they lacked the lived in world look of Lucas' film. It was that dynamic that allowed audiences to fully immerse themselves into the film.
RIP Harlan Ellison