CHJ, Calzaghe in some respects only has himself to blame. He wasted his god given talent. He never unified, never sent up in weight to try to fight the best, and never fought away from home. If an American did the same thing they would be scrutinized just the same. Bernard Hopkins wasn't popular with the experts at all until he defeated felix trinidad, and recieved much of the same criticism that Joe gets. IMO if joe really believed he was great, he should have chased a fight with both Hopkins and more importantly gone up to fight Roy Jones. A win against Roy pre Tarver would basically have made the top (or very close to) p4p fighter in the sport, and cemented his legacy as an ATG.
Calzaghe had chased Hopkins, to the point where Bernard had agreed in principle to sign for a fight, until he upped his demands to beyopnd what Frank Warren would pay. This was back around 2000 too.
They are unlikely to be P4P number one after 3 fights, due to the learning curve of the sport. Joe Calzaghe started heading towards becoming P4P number one after Robin Reid fight - a competitive fight and a vital learning experience.
Roy Jones is a top 5 all time P4P fighter and greatness grows over time. ATG is about greatness, not how good you are, so vastly, vastly, vastly inferior fighters to Roy like Willie Pep get put above him. One weight champion Pep.