This is the best statement yet of the anti-parity side of the pro-players side

. I disagree that it follows that the parity system is not important for the NFL.
There are two reasons that parity is more important for the NFL than it is for the other leagues.
1) In the NFL every year there are teams at 14-2 or better and 2-14 or worse. 14-2 is .875 winning percentage. If a baseball team did that they would be 142-20. The losing teams would be 20-142. An NBA team would be 72-10 ('95 Bulls!). Football is just a different game, it has more extreme outcomes
with parity than baseball or basketball
without! What would the NFL see without parity? Many games whose outcomes were in no doubt whatsoever. Games would regularly be decided by 60-70 points. Yes when the Giants played the Cowboys it would epic, but how many 64-0 games would you watch with backups playing the whole 2nd half?
2) The NFL needs fans to watch games other than their home team. The NFL can only profit 16 times a year off a fan who only watches one team. Those other games need to have interest too. MLB, NBA, NHL don't need that to succeed. They only need fans to have passion for one team.
I personally think the other leagues would be more popular
on the whole with parity systems in place but I can see the arguments against that point. For football I think it is critical.