QB Really That Important?

I've been kicking this around.  Look at the names on this list:

Adrian Peterson
Steve Hutchens
Matt Birk
Bernard Berrian
Bobby Wade

Jared Allen
Pat Williams
Kevin Williams
Darren Sharper
Madieu Williams

Chris Kluwe
Ryan Longwell

There is more talent on one side of the ball than on the entire team of more than half of those in the league.

What is the problem?   Does it really come down to those two little initials on the position we have been unable to find a guy that has the credentials of those listed above?

The reason I ask, is it seems that all of the good QB's are no longer around.  The league used to be full of them.  I mean good ones.  Favre, Aikman, Young, Kelly, Elway, Cunningham, Moon, Marino, McNair, etc.

Now we do have some.  Manning, Brady, Roflberger, and I'd be willing to consider the other Manning in there.

Here's my thing.  You could throw in a bunch of other names, but I don't think it would complete that list like the one above.

So, without the cadre of names like we had before, how are some of these teams able to get it done, and why do the Queens find it so difficult with the supporting cast.