It usually works out that the 4 top seeds are the regular season champs of their conference.
Are you talking basketball or football? Either way that is not true.
You can't look back and have Oklahoma, Texas, USC, UCLA, Oregon, Washington in the Top 4 and say see it works, those conferences are represented. The teams will all be gone from their current conferences. The PAC is gone and the B12 Champ isn't likely to be Top 4. Even the ACC if the Top regular season team loses, the Champ is not Top 4.
Heck just last year the Top 4 conference champs were ranked 1st, 2nd, 7th, and 8th.
1. UGA vs (8. K State vs 9. Penn State)
2. Michigan vs (7. Bama vs 10. USC)
3. Clemson vs (6. TCU vs 11. Tennessee)
4. Utah vs (5. Ohio State vs 12. Tulane)
The 5 seed (best non champ) some years will have the easiest path to the Final 4. They will end up playing the worst conference Champ (G5) and then the worst P4 Champ.
Using the current rankings and future conferences you get...
1. UGA vs (8. Oregon vs 9. Tulane)
2. Ohio State vs (7. Texas vs 10. James Madison)
3. FSU vs (6. Washington vs 11. Bama)
4. Arizona (17th) vs (5. Michigan vs 12. Missouri)
Does Michigan not have the best path?