Not to ruin a perfectly good conspiracy theory, but its possible that the FBI/NCAA cloud hanging over those teams, plus, Kansas and Oklahoma State, might affect their recruiting/retention and play through the season, or at least be a distraction for the coaching staffs. Not to mention COVID issues and worries about COVID.
Although Kansas and Okla State made the tournament, for the first time nearly a decade Kansas did not dominate the Big-12; they struggled on the road all season.