I guess the bottom line for me is this: If the decision makers are closely following a quantitative index that consistently is giving one P6 conference far more tournament bids than any other but the performance of that conference is not justifying those bids, then you have to consider whether there is a consistent bias in that index and whether you should weight that metric a little less.
Again, I think decisions should be made weighing all sorts of evidence and I don't think any conference deserves 9 bids unless the evidence clearly establishes that the conference is head-and-shoulders above the others. I also don't think that these excess bids should all go to other P6 conferences. It seems to me that two or three more mid-majors should get tournament bids in most years.
The metric might be dead on. Remember the final three teams that got in for the Big Ten did so as two of the Last Four in and an 11 seed. That group has gone 3-2 so far, including a Sweet 16 berth. That, to me, proves the metric is correct.
So, if we are to question the metric, I guess we would have to determine if teams like Wake Forest, Texas A&M, BYU, Dayton, etc., would have potentially done better if given those spots instead? It is certainly possible, but not guaranteed (and in my opinion doubtful).
The Big Ten got 9 teams in, there were six no doubters. Illinois, Wisconsin, and Iowa disappointed. #7 seed Michigan State gave #2 seed Duke a tight game, #7 seed Ohio State gave #2 seed Villanova a tight game.
I actually think the Big Ten was seeded about right, and if you go by "chalk" should have had three in the Sweet 16. They have two. Illinois and Wisconsin are disappointments, although Wisconsin suffered a catastrophic injury, but I didn't like them to advance all that far either way. Iowa was a disappointment, but purely by seed (based on the metric), was not supposed to make the Sweet 16.
I don't think the tourney was as much of a disaster for the Big Ten as most are making it. The Big Ten, Big East and Pac 12 all got two into the Sweet 16. All suffered some upsets. The Big 12 and ACC have three in the Sweet 16. The Big 12 was generally regarded as the top league in the country and it showed, although defending champ Baylor was a disappointment. If there was a disaster in the tourney, it was the SEC by a LARGE margin.
And, the crazy thing, if we started over with the same field and the same matchups, and played it again, the Big Ten might get Iowa and Illinois and Wisconsin into the Sweet 16. You just never know.