He's suggesting that putting football in the MWC would cause our revenues to drop to levels similar to G5 schools. When BYU was part of that club, its revenues were consistently higher than any other program. It's silly to suggest that there would be a $20 million revenue hit were BYU to re-join the MWC. There would be a revenue hit of $3 million or so which is not insignificant.
There are a lot better cases to be made for staying independent in football - he just wasn't making them.