Take a look at the numbers for the Big 12 Championship and the AAC Championship with Cincy v. Houston. Both of those outdrew the ACC Championship, and the Big 12 game doubled the Pac-12 Championship with Utah-Oregon. This is true for the rest of the season as well. The numbers for the Big 12 without Texas/OU aren't horrible and the new additions help with that both in ratings and markets.

Generally agree with the eventual takeaway (that the Big 12 is in a stronger spot), but some of these arguments are a bit biased.

You point out that Oklahoma St/Baylor conference championship game outdrew the Utah/Oregon game by a fair amount. Which is true. But part of that is also likely that Baylor/Oklahoma St was at noon (ET) on Saturday, while Utah/Oregon was a pretty terrible 8 PM Friday night start. Also, that Oklahoma St was possibly in contention for a CFP berth gave it more interest.

A PAC12 apologist could counter by pointing out that the PAC12 NY6 game drew nearly as much as the Baylor and OK St NY6 games combined.  But that also doesn't tell the whole story.  Oklahoma St (the best Big 12 draw) got a much weaker draw than Utah and Baylor (Ohio St and Notre Dame, respectively).  And while both the Oklahoma St and Utah game were exciting to watch, the Baylor game was a bit of a snooze-fest most of the game (7-7 going into the 4th; I like games like that, but I also enjoy soccer - most people prefer the offensive fireworks)

Looking over every widely televised regular season (so no conference championships or bowl games) game against a P5 opponent over the last 5 years, and then removing Texas/Oklahoma/USC/UCLA games, here's the average viewership for each team in the Big 12 and PAC12 (plus BYU, didn't include Cincy, UCF, Houston due to small P5 opponent sample size)

Average viewership for P5 regular season games (no conf championships or bowls) with UCLA, USC, Texas, Oklahoma removed

1. Oregon 2.31
2. Washington 1.78 
3. Washington St 1.67
4. Stanford 1.65 
5. Colorado 1.60
6. Oklahoma St 1.47
7. Arizona St 1.35 
8. BYU 1.34
9. Utah 1.25 
10. West Virginia 1.12 
11. Iowa St 1.10 
12. Cal 1.07 
13. TCU 1.06  
14. Oregon St 1.02 
15. Arizona 0.97
16. Texas Tech 0.84 
17. Kansas St 0.78 
18. Baylor 0.73 
19. Kansas 0.47 

Ironically, the two who are BY far the most hurt by removing bowl games and conference champiosnhip games are Utah and Baylor.