We don't count AFL championships because they aren't NFL championships...really? We don't count USFL champs either.
And nobody can seriously think that an AFL champion would have been able to give the NFL champs a competitive game in the early days of the league. And this isn't about the Packers. The Bears, Colts, Giants, Rams, etc all had great teams in 50s and 60s. I'm thinking that the toll on the players bodies was greater in 12 games at that time than the 16 games now with all the substitutions and the lack of hitting in todays game.
But, obviously, we will have to agree to disagree.