No matter how high the hype is built, some people will still be satisfied that it's there, especially if it's close enough to it's older appearance. If "flying cars" ever happens the way it's usually portrayed, people will remember it in a special way, even if it's terrible.
Some people might like the new design if the character has one, or their interactions with the characters and the newer ones if they're relevant enough. They might have a shot type or quotes that people love. Applies to all of them, but for the hyped ones, it'll still have "finally happened". That's good enough for a lot of people.
Unless it's done terribly, like making them into a completely different character that's practically just dressed similarly.