I don't think you know what "parity" means as the term is commonly used.
Yes that's the point I am making. NFL teams who suck year in and year out are poorly run teams with inept coaching, poor fundamentals, etc, etc. None of them are losing simply because they are being outspent.
So wait a second, is a dynasty a good thing or is it a bad thing? Make up your mind. Joe Gibbs won 3 Super Bowls and you praise the system. Kansas City wins 3 Super Bowls and the system sucks.
That's got nothing to do with whether or not there is parity. QB is the most important position in all of sports so obviously the teams with great QBs are going to have the inside track to winning.
BTW, Nick Foles won a Super Bowl recently. So don't say it can't be done by mediocre QBs.