In their primes Federer would eat Djok’s lunch (which he routinely did up until ~2012). He’s catching both of them at the end of their careers and yet they’ve still pulled off some wins.
So Djok can have the lead for weeks at #1 but he doesn’t have a quality opponent like Federer did with Nadal (196 weeks at #1).
IMO, Federer -> Djokovic -> Nadal.