Because after watching the committee do this for 10 years, the #1 thing that helps is having great win against other teams they ranked highly. If Kansas State was ranked ~12th then I would felt very confident that BYU would be very high. But now Kansas State likely falls to the 18-25 range which helps, but gives BYU’s spot a lot more latitude.
Of course, it made the chances of going to the championship game higher, which I get.