Including this season with the "four years of pure mediocrity" Izzo's record is 128-59 and the Texas record is 108-56.
As others have said, 99% of fans would be extremely happy to have had Izzo. While Izzo has been at Sparty Texas is now on its fifth coach, as is Pitt.
I would have loved me some Tom Izzo, 733-300 record, as my coach as opposed to the shit we have been fed.
Every coach has some bad seasons. Dean Smith had 5 double-digit loss seasons, Coach K had 8, Larry Brown had three in five seasons at Kansas. Bill Self has had four in 22 seasons. Izzo has 14. Jimmy Boeheim had 22. Roy Williams had 11. Knight had 18. Pitino has 12. Calhoun had 19. Calipari with 12, etc etc etc.
I don't know what the future holds for Izzo, nor do I really care but, I'd guess he has a few more seasons in him and if he sticks around he could end up in the top-12-15 all-time. That's pretty darn good.