ESPN, hometown network of the Patriots, keeps saying the AFC is better.
Yet, in interconference games each conference has won 8 and lost 8.
Sounds like parity to me.
Look at the current top teams.
The Patriots have not faced an NFC team yet. (Okay they will only face the NFC East.) Denver hasn't faced an NFC team either. Indianapolis has faced the Saints. Pittsburg won over the 49'ers but lost to the Cardinals. The Titans beat the Saints and Jaguars defeated the Falcons.
In the NFC the Cowboys have beaten Miami, The Packers have beaten San Diego, Seattle has beaten Cincinnati. Tampa Bay has not played an AFC team. Current wild card Detroit beat Oakland and Washington beat Miami.
I don't see it as clear cut as the propaganda being spewed from East Coast media outlets.