In many instances that would take the risk out of the conference championship game while the other conferences would still have it. The winner of a championship game between a 1 loss or an undefeated vs 1 loss team would almost be guaranteed a playoff spot where another P5 team with a great record would have a lot to lose and little to gain if it was playing against the winner of a weaker division and that team didn't have a top 15 ranking.