I am a Ron Zook apologist so I get some of that sentiment (btw I'm not @LordsThadChair). I think Zook and Weber got screwed over by Mike Thomas, in the sense that they were fired the second the ink dried on Mike Thomas's contract and there was never anything realistic they could have done to save their jobs. While Mike Thomas thought Illinois should be winning championships it was more important that "his guys" were doing the winning. If you gave Zook a shot of truth serum he'd probably admit that when he didn't get an extension after 6 wins he knew he was facing an unfriendly administration and the pressure of playing for his job got to him in the second half of the season.
So while Zook probably was never going to reach the heights of the 2007 season, the combo of Zook/Petrino/Koenning seemed stable enough for 5 to 7 wins a season. We probably would be grasping for air in the crowded middle of the B1G (the 6th - 10th best range) but that seems preferable to the "can we finish outside the basement" tier we currently find ourselves.
I think it is true that since we fired Zook, Illinois has desperately wanted to get back to that level of mediocracy. I think people forget that when you reach that "we reliably win 6-7 games a year" level you still have flaws. Of those 5/6 losses, a few will be games you should have won if you had a better secondary. It'll be a program that never seems to find decent RB's/LB's/whatever. Show me a team the consistently wins 6 games and I'll show a fan base that honestly believes they could have won 9 that year.
In all honesty, in view of the past 11 years, how many 5-7 seasons would you have tolerated for just a single "winning season"