It's all subjective when you get down to it, but there will have to be some input by humans on who the cream of the crop is. At least on who gets to play. I think most people can agree who the best 4/8/16 teams are. Then, let them all control their destiny from that point on.....
If we were talking about the humans choosing the National Champion, just 1 team of all 120, I would be inclined to agree with you. But looking at wins, dominance, SOS, etc - it shouldn't be that big of a deal to choose X amount of teams to play for it all.