30+ years of a team that could possibly, hypothetically, get left out of a 12-team tournament. The one example.
But not only is it not clear that being left out of NY6 means they would get left out of a 12-team playoff that has tons more significance and fan interest, but you also overlook (or don't realize) that CC didn't even play the Sun Belt Championship game that year. The game got cancelled because of Covid issues CC was having. That's not anybody's fault, but CC was scheduled to play #19 Louisiana in that game. If that game had happened, and if CC had won that game (another top-20 victory in an otherwise weak schedule), they might have gotten into an NY6 bowl.
So, even with your one example of a team getting left out, it's not even clear that they would have been left out of NY6 under normal circumstance, much less that they would get left out of a 12-team playoff.
Back to the drawing board for you. Enjoy your pretzel.