Federer played tennis that fooled us into believing into the greatness of man, the genius, the renaissance, the ideal of what man can achieve artistically. He is modern day Beethoven in athletic form.
Nadal then matched him and fooled us into believing in the strength of man, the brawn, the fighting spirit, the willingness to go all-out. Those dueling capacities, the genius and the worker, is a very compelling rivalry.
Then Djokovic when he came along cut a different path. He immediately showed through his tennis that the one defining characteristic of humans is not their genius or strength, but their mortality, their frailty, their weakness. That everyone, everyone is human, everyone has flaws.
Good take from Toni.