SOS is one aspect of determining the best teams to qualify for the playoff. SOS is not the end-all be-all in making the playoff. Miami & FSU played in the Big East and the ACC respectively for a long time, yet no one questioned that they were the best teams in CFB at their peaks. The 49ers played in a terrible NFC West for decades, yet somehow they still managed to win 5 Super Bowls. If BYU is dominant, they will be considered among the best teams in CFB.