When ESPN and Fox said no thanks in renegotiating the tv deal the writing was on the wall. I think they are aware that joining the SEC would significantly increase the per team value it makes sense to jump.
When talking to recruits does playing the bottom 8 of the Big 12 sound as appealing as any 8 in the SEC? The Big 12 overall has become stale and isn’t poised to close the gap with the SEC. Looking at 2021 national recruiting OU signed 3 top 50
players, Texas 1, the rest of the Big 12 zero.
In the SEC, there is only 1 program that is routinely better than both schools. The more likely way to catch them is to join the conference.