Based on what exactly.. being the only undefeated Power 5 team? Regardless of they looked, they did the one thing that no other team could claim & that was win all their games on the field. You could not leave them out or it would have made the whole playoff a sham.
Based on opening my eyes and realizing the playoff ranking formula is a lot different than the old BCS-formula, or even pre-BCS. In bygone eras, FSU would have gone wire to wire number 1. But that's old thinking. Undefeated teams drop in the rankings now. They use the eye test more heavily than any other time, it even at times trumps a win/loss. So yeah, based upon shaking off outdated thinking and seeing that FSU was being punished for average play. They went from #2, firs ranking, to #4 on the penultimate ranking with every reason to believe that they should have dropped to #5 based upon how every other team was playing. My personal opinion is the ranking committe fell to mounting pressure, which is why they decided to "right" the TCU situation. They way they chose, had less blowback, but it looked to me they couldn't stick to their guns with how they really felt. But, first mistake was publishing a poll every week. They let out too much information, though it was good if only to see how ranking criteria has definitely shifted.