Winning your conference, nor making your conference's title game "earns" a shot at playing for the national title. Nor did Oklahoma St. make a conference title game either because the Big-12 doesn't even have enough teams to host a conference championship game.
The "must win your conference" argument is ridiculous. Fact is, most teams that do win their conference have no business playing for a national title and the SEC proves that every year. All conferences are not equal, or even close.
LSU destroyed the Pac-12 Champ and the Big-East Champ. Neither Oregon nor West Virginia were national title worthy. Hell, the 5th best team in the SEC (South Carolina) destroyed the ACC Champ (Clemson). The Big-10 Champ (Wisconsin) lost to the Pac-12 Champ (Oregon) in the Rose Bowl. If we've already established that Oregon wasn't national title worthy, neither was the Big-10 Champ who lost to 'em.
Alabama finished 4th or 5th in the SEC the year before and destroyed the Big-10 Champ Michigan St. 49-7 in the Capital One Bowl.
Oklahoma St. lost to a 6-6 team, and should've lost to Stanford in the bowl game if the freshman kicker for Stanford makes a chip shot field goal.
The Conference Champion argument is nothing more than hogwash. The SEC has about 3 teams in it every year that would win every other conference out there, and go undefeated doing it.
Not only was the top 2 teams in college football this year both in the same division in same conference.... the 3rd best team in the country was also residing in the SEC West. Arkansas' only two losses were to LSU and Alabama, and beat the team (Kansas St.) that scored 45 points on Oklahoma St.'s pathetic defense and almost beat 'em.
The conference champion argument will never happen under any system because it eliminates Notre Dame. Their belligerence has been a pain in the a** of college football for decades.