I think a better way to look at it is to have a clear distinction between matchmakers odds or the betting line, and rankings.
It's not all that uncommon to see a fight where the higher ranked fighter is the underdog, sometimes by a lot. How can this be? The ranking is based on what fights they have won lately, where the odds are based on how good we think they are.
This is why the champion is always at the top of the rankings. It would demean the significance of the belt if you started ranking other Fighters above them because you thought they had better wins against more quality opponents.
It's like the middleweight division right now. A lot of people don't think that the champion is the best fighter in the division. If rankings were based purely on perceived skill and quality of recent wins, you might put Bobby knuckles above him.
So I don't necessarily think that the rankings show who is the better fighter, that's what the betting odds are trying to do. They're more like a waiting list for the title shot