Top 3 teams in the old MWC were BYU, Utah, TCU.
Top 3 teams in the then-B1G were Ohio St, Michigan, Penn St.
Those things are still the case for the Big 12.
Now the Big 12 certainly has better names around that group than was the case in the old MWC. Upgraded from Air Force, San Diego St, Colorado St and New Mexico to Oklahoma St, West Virginia, Iowa St and Kansas St
But at the same time the B1G upgraded to USC, Oregon, Washington and UCLA. The SEC upgraded with Texas, Oklahoma, Texas A&M and Missouri (I guess)