I'm not sure that I actually believe this. I agree that the committee is going to favor the B1G and SEC, but I think that's their secondary concern - they are going to favor brands and TV eyeballs. It may take time, but I think they're going to find that viewers don't care about a rematch with the 4th/5th place team from the B1G or SEC and viewership will fall relative to seeing an extra team from the B12 or ACC. The ESPN talking heads can talk all they want and try to spin it, but at a certain point people will not tune in.
So we have 6 at large spots each year, 7 if ND isn't good. Let's just look at the SEC and think about their historical performance - you've got 5 teams that have won or been in the championship in the last 20 years in Georgia, Alabama, LSU, Florida and Auburn. Auburn is not a perennial challenger, so you throw them out. Add Texas who will be up there if they can continue to compete at the level they are now. On the fringe maybe you have a team like A&M who has some championships in the distant past. Those are the brands who will get eyeballs. The SEC has averaged 3.6 teams with 10+ wins in each of the past 5 years (not counting 2020). So I don't think you're getting a 9-3 SEC team in the playoffs - but you probably are getting 4 SEC bids. The 9-3 2023 LSU Tigers (IMO) probably don't make it over the 2023 10-2 OU or 10-3 OSU because more people are going to care about the 2nd/3rd place B12 team than the 5th place SEC team. The committee might not see it right away, but they will over time when they see poor numbers for weird SEC rematches featuring teams that were never really title contenders vs more interesting matchups.
If you look at the B1G over the same period, they've averaged 3.4 teams with 10+ wins. But who are the brands? Really you have only OSU and Michigan in the last 20 years, though you can add Oregon and Washington now as teams who have been in the playoffs. Personally, I don't see the B1G brands below OSU, UM, and Oregon as strong enough to carry an unjustified playoff berth. If Nebraska has 10 wins I think they also get special treatment, I don't see it for a 9 win Nebraska team. I think the B1G gets 3 most years. National level support and interest just is not there beyond those top 3 brands. Sure, if someone like MSU, Penn State or Nebraska jumps up and makes it into the top 2-3 teams they'll get in.
Anyway - TL;DR: I think 10-2 or 10-3 SEC/B1G teams get in over non-champion 11-1 or 11-2 B12/ACC teams. I don't think the 9-3 teams will jump the conference runner up if they have 11 wins. Just based on performance over the past 5 years, in most years one or the other of the SEC and B1G will have only 3 teams with 10+ wins, leaving one for the best non-champion ACC/B12 team if they have at least 11 wins. Depending on relative brand value of the teams under consideration, a 10-2/10-3 B12/ACC team may be able to get in over at 10-2/10-3 SEC or B1G team. For example - 10-3 conference runner up FSU, Clemson, Utah, maybe even ISU/KSU/OSU would have a good chance at getting in over 10-2 Illinois or Rutgers, but probably not over Penn State, Nebraska, Texas A&M etc.