The powers that be are certainly pushing the SEC and Big Ten as the two "power" conferences. Even with that please explain how i.e. the Mississippi schools, South Carolina, Missouri, Kentucky, Vanderbilt--even schools like Tennessee and Florida fit in with the super earning so called "power schools"? What about Rutgers, Maryland, Indiana, Purdue, Minnesota, Illinois, Northwestern, Iowa, Nebraska? Its really about 4 or five schools that are driving all this and they can't play just themselves. Wait til Texas and OU are having regular 7-5 or worse seasons each year. Think they'll be happy about that?
That said, the BIG 12 is not in a worse position than the PAC or ACC. The PAC just lost their only two relevant national brands (yeah, Oregon and its Nike money have tried to buy their way into that, but haven't really succeeded). They have paid out lower amounts than the BIG 12, have lower tv ratings than the BIG 12, and far less fan interest than the remaining and new BIG 12. No way to claim they are in a better position--especially since BIG 12 schools have significant time remaining in contracts as well as new media rights negotiations upcoming which are being said to be looking far better than the initial doom and gloom projections.
The ACC is going to lose schools too, right now no one is trying to get out of that GOR but its coming once the Big Ten announces the money and duration of their new agreements. What's an ACC with already low contracts going to look like without Clemson, FSU, etc.
The PAC is more likely to lose more schools going forward than the BIG 12 as well.
The BIG 12s expansion and revenue options are growing and with a new contract coming these changes could be significant.