I'm a Loyola fan, and I'm always happy to take a shot at the system. First of all, 5A and 8A have nothing to do with it. The seeding system across the board is flawed. Not just in the 1-16 classes.
Loyola was the #1 seed in 8A and they faced the #32 seed in West Aurora. WA deserved to face a true #1 in Loyola because WA was 5-4 with the least # of playoff points in all of 8A. In round 1, Loyola basically played to its seed and WA played to its seed. Result? Loyola won 31-0. In that case, the system worked.
However, in 5A, the system failed...badly. Westinghouse was the #1 seed in the north bracket. Glenbard South was the #16 seed in the north bracket. Glenbard South beat Westinghouse 42-0. 42-0!!!
Glenbard South was the 5-4 team with lowest playoff points in that 5A north bracket. Why should they be allowed to advance simply because of the luck of the draw?
To a lesser extent, but also in 5A, Solorio was a 5-4 #15 seed beating #2 seed Lindblom.
Imagine you are the 6-3 Rich Central Olympians. You were seeded #12 in 5A and you lost a one score game to the #5 seed team. You had a better record than Glenbard South and Solorio. You could have won big if you could have played Westinghouse or Lindblom. But, today, you are turning in your equipment while the kids from Glenbard South and Solorio are playing again this weekend...solely because of the luck of the draw.
I don't have an answer as to how seeding could be done better. But I do know a flawed system when I see one. The seeding debacle in 5A this past weekend is not something that the IHSA can look at with pride.