Not disagreeing with you about Texas vs Oklahoma but going forward, I think things will be different, perhaps very different. I don't think it's smoke & mirrors at all.
1. Texas and Oklahoma for the first time ever are now in the SEC. Will they still be all that? I'm not so sure. First, they will likely have more losses than before. Second, it's the SEC. Will SEC fans be so quick to accept them rascals? Third, Alabama is the king. Alabama-Auburn, Florida-Georgia, those are SEC rivalries.
2. I know if we were in the Big 12 I'd sure be watching a lot more of Okie State, Arizonas, Kansases, Colorado, Utah. Just as Cincy, Houston, UCF fans are likely doing. Long time Big 12 fans may not care so much about Texas-Oklahoma anymore. So that rivalry may have lost a lot of fans right there in its own footprint.
3. UConn is sitting here as one of the premiere blue-chip programs in the country. One of our biggest rivals? Creighton. Freaking Creighton! 10 years ago I didn't give a rat's ass about Creighton. 20 years ago I couldn't find it on a map. Point being, conferences can create great rivalries and the Big 12, top to bottom, is an excellent conference with no dead weight.