I think all of this is skewed by the fact that the four corners coming in played games against Oregon, Washington, USC, etc.
The staying Big 12 teams played games against Texas and Oklahoma. All of this makes the new Big12 look better. I expect these numbers to drop despite the PAC-12 network going away. Those games will be replaced by ESPN+.
I'm VERY worried about this, actually. Week 13 Big12 numbers saw ISU-KSU hit 3.3M, with BYU and OSU hitting 2.4M (per sports media watch). Utah-Colorado obviously didn't show up at all due to the P12 broadcast. Arizona-ASU was 740K.
Any article I can find on a well viewed new BIG12 game was played against a B1G or SEC team. I mean, what do you all think the highest rated Big12 game will be next year?