The NFL officially considers the NFL Championship at the same level as the NFC Championship - likewise the AFL Championship at the same level as the AFC Championship.
Hence - it is why each is called a Championship and a Trophy is awarded for each. The Lamar Hunt Trophy for the AFC and the George Halas Trophy is awarded for the NFC - which became effective in 1984.
The NFL Championship and the Super Bowl ARE different things. If you have any question to dispute that - ask the Baltimore Colts and Minnesota Vikings - who won the NFL Championship in 1968 and 1969 but lost the Super Bowl.
NFL Championships were championships that were awarded for a long time - not won in any championship game. When there was a championship game, there was no playoff - it was a meeting of the two best regular season records from two "conferences" and was played on a rotating home field advantage - not like the nuetral field Super Bowl site. In addition, ties were very common, but were thrown out of the equation in determining best record, so a team could win the regular season and play for the championship despite having a worse record than teams finishing above them.
There is a reason that the Super Bowl is held with more regard than the NFL Championship. The Patriots had to win 9 games vs. legitimate competition to win their 3 Super Bowls, the Browns had to win 5 games to win their 4 NFL Championships - with only 1 on the road.
Since 1933, the NFL has had a "League Championship Game" and it still has one "League Championship Game" (now, AKA the Super Bowl). Those games were played between the winner of the "Eastern/American Division Conference" and the "Western/National Division Conference." I don't think you could cite any NFL source to support your statement that the "NFL officially considers the NFL Championship at the same level as the NFC Championship." The NFC Championship is a conference championship; the NFL Championship is a League Championship, contested today, as it has always been, between the winners of the League's two conferences. Those are two different things.
The fact that the League is larger now after the merger and thus has a playoff system to crown its separate Conference champions with appropriate trophies before it crowns its League champion, doesn't diminish in any way the value of League Championships before the current system went into place.
It seems arbitrary and more than a little unfair to say, for example, that Vince Lombardi's three NFL championships prior to 1966 were worth less than his two NFL Championships in the SB era.
He still had to beat the best that Professional Football in the US had to offer to earn them.
I was doing a little research the other day and discovered that there were no less than 15 future Hall of Fame players on the field or on the sidelines in the 1960 NFL Championship game between the Eagles and the Packers... Lombardi's only loss in a League Championship game.
Whatever the path to that game, a team still had to beat the best to win the title. I don't think that any Super Bowl has had as many HOF players involved as that game. Would you want to tell Chuck Bednarik and Paul Hornung that that game wasn't as great a test of the best as a ring won by, say, Trent Dilfer? Even in their old age, I don't think I'd want to be within swinging distance of either Bednarik or Hornung if I tried to make that argument.
Yes, the games were played at alternating home stadiums and yes the playoff run was shorter, but in the end it was still the best against the best and that is what a League Championship is and that is what makes it impossible, in my opinion, to define one era's in lesser terms than another's.
Was the 1958 game between the Colts and Giants any the less a test of greatness because it was played in New York by rotation and the two teams had "only" come out first in smaller Conferences?
Would you seriously have tried to tell Johnny Unitas or Raymond Berry or Frank Gifford or Sam Huff or any of the 17 (!) future Hall of Famers who were on the field or sidelines that day that it wasn't as significant a contest because it fell in 1958 and not 1968? Has any team in the SB era won a game when 17 HOF'ers were on the field or sidelines?
The 1958 "NFL Championship Game" (resolved in OT) isn't called "The Greatest Game Ever Played" for nothing. But, using your logic, you would put any of the Super Bowl era Championships over it because.... I don't think you even want to try to make that kind of argument and if you do, I doubt you'd want to make it in front of any of the guys who left their blood and tears on the field that day.
In baseball, too, the path to a ring has gotten longer and more complex. For many years there were two leagues of eight teams, barnstorming the country for 154 games. In the end the World Series was contested without a playoff. Does that diminish any of those other championships? Would you tell Ruth or Cobb that their championships were worth less?
I guess we disagree.