You're running a disingenuous comparison. The cap has only been around since 94 or 95 in the NFL. And prior to the 90s NHL salaries were pretty low across the board (Gretzky didn't even make a million bucks until he went to LA, greatest layer in the history of the game was playing for 900 grand). A good comparison time is 94 up. That's where you see the 2nd age of dyansties took over in the NHL and you get Colorado, Detroit, Dallas and Jersey alternating Cups, and the age of dynasties passed in the NFL and you could never really guess who was going to win it all, until Belichick cracked the code.
"You're running a disingenuous comparison."
Really? How is it disingenuous to compare the major sports with regard to your pointed reference to the need for a hard cap in order to promote competition, despite the fact that each of those sports owners uses a different way to fund themselves?
But, let's see about your premise that "A good comparison time is 94 up."
In the NBA: 5 teams since the '94 Finals.
In the MLB: 6 teams since the '94 World Series.
In the NHL: 5 teams since the '94 Stanley Cup.
In the NFL: 8 teams since the '94 Superbowl.
In NASCAR: 7 drivers since the '94 season.
I'm very curious about how you extract the benefit of a hard cap from even the last 10 or so years? Upon what are you basing your opinion? Surely not recent sporting history.