They might have just got rid of some of the grain, or maybe they just went back to the negatives. The film isn't very old and had CG in it, don't forget, it shouldn't really look dated.
But yeah, I agree with your point: films are what they are. A film from 1977 should look like it was from 1977. Now, this doesn't mean that it should be super grainy and all contrasty, when you go back to the negatives they are surprisingly crisp compared to how we expect them to be.