>>120716746Really, the only thing people wanted out of Grievous in the movie was for him to live up to the expectations set by the ancillary media of the time in terms of consistency, not have him duel another 5 Jedi at the same time or tell us about his backstory or something of like that, because anybody who was familiar enough with the previous installments knew Lucas was not somebody who liked indulging in plots secondary to Anakin's arc.
But instead, George went all the way to create an almost completely different character, and then years later doubled down on it with the second Clone Wars series, practically ruining his reputation among casual audiences and nullifying any chance for the character to be taken seriously.
At least that's how I see it.