Nas' ability to win a feud against one of the most successful rappers of all time demonstrates his remarkable skill. Both Jay Z and Nas released diss tracks about each other. In a poll from the Hot 97 radio station, 58% of listeners said they preferred Nas' track, "Ether," over Jay Z's "Supa Ugly." Jay Z may be a business mogul, but any crown he may have held for the best rapper of all time now belongs to Nas.
Nas' ability to defeat Jay Z with "Ether" demonstrates only that Nas is better than Jay Z, not that Nas is the best rapper of all time.