There is nothing wrong with staying youthful. But is a state of mind, not a case of dressing up in your son's clothes and copying his hairstyle, or pretending the haircut you had in the 70s is still acceptable.
Confidence and self acceptance is what makes a man attractive and successful. Don't move with the times and you will end up looking more than a little past it, just like Robert Plant - a man with a more feminine cut than his singing partner Alison Krauss.