The football expansion effort is unfolding at a time of sustained tumult in college sports, especially for the industry powers — the 10 Football Bowl Subdivision conferences, as well as Notre Dame — that jointly run the playoff and distribute shares of its income to universities across the country. As television money is increasingly raining down on leagues such as the Big Ten Conference, which last month announced a record-setting suite of media contracts that will pay it at least $1 billion a year, and the Southeastern Conference, other leagues fear being left behind, in perception or reality.
Beyond business rivalries, the leagues and the industry that dominate in the public imagination have faced legal and political setbacks, particularly around the rules that restricted unpaid college athletes for generations. Still, for many fans, antitrust law matters far less than how to crown a football champion.
The playoff is the successor to the Bowl Championship Series, which used a complex formula to help determine matchups for elite games, including the title contest, for 16 seasons. The four-team playoff system debuted with the 2014 season and offered football devotees a new way to become baffled and infuriated by rankings.
There would be ritualized gripes about the conclusions of the committee charged with ranking teams, of course, but the tournament’s small size also left it vulnerable to complaints about the limited number of teams able to compete. (Although the N.C.A.A. manages the postseason for Football Championship Subdivision universities, which often have loyal local followings but little national renown, it has no control over the playoff that draws powerhouse brands such as Alabama, Clemson, Ohio State and Oklahoma.)
Alabama has won three national championships in the playoff era, and Clemson has won two. Georgia, Louisiana State and Ohio State have one playoff title apiece. Deepening the sense of exclusion, just 13 of the 131 F.B.S. schools have made appearances in semifinal games, and at least one Power 5 league is currently guaranteed to be left out in any given season.
The Atlantic Coast, Big 12 and Pac-12 conferences all missed the playoff last season, with the Pac-12 enduring its fifth straight year of not receiving an invitation.