It’s a scam. Always has been. Always will be.
I think this kind of skips the strongest argument actually, because I think your diagnosis is quite right, that the process goes 1. recruiting rankings = 2. preseason rankings = 3. strength of schedule inflation
However, in the early to mid 2010's, it was just flatly true that the SEC had schools all the way to the lower middle class of the conference that just went much deeper into their roster with great athletes than the rank-and-file elsewhere. It didn't show up on the field every single time they played nonconference games, but it did show up a lot, there were top stars all over the country, but in the parts of the game where the rotational depth of your front seven, for instance, was critical, those SEC factories just outclassed everybody else.
How did they get and keep those guys? The slander of the time was right, they were paying them!
Well, NIL has changed everything, everybody else can pay their guys too, and now that guy who was the 3rd DT at Auburn has better and higher paying options elsewhere. The larger and wealthier alumni bases of the Big Ten have arrived at the party, and the results on the field have changed accordingly.
But these poll and committee voters are operating with too much inertia, they are huffing the fumes of recruiting rankings from ten years ago.
I am not generally a fan of this kind of conference politicking, I don't care to play lawyer for our hated rivals and I feel like this stuff all tends to work itself out over time. But Bama ahead of UCLA and Tennessee ahead of Indiana are bad ones that can't be rationally justified, there's no two ways about that.