Hewitt's initial success (taking the underachieving Cremins leftovers to the NCAAT then the great recruiting class leading to the very good 2004 and 2005 teams) was followed up by a distinct change in his attitude toward the press and the public.
He became intolerant of criticism and started making statements that seemed to blame the school for any problems with his teams. After his first five years he still would get some talented players but those teams all had glaring flaws (poor ball handling in particular) that led to disappointing outcomes. Meanwhile, he spoke out on behalf of the Black Coaches Association while his team wasn't playing well, which really stirred the pot of anger that had started to build. Many felt that he didn't accept the reality of a degrading program, while wasting time arguing with the local sportswriters and lashing back at criticism.
Once many got into their minds that he was a bad coach they started to re-write history in order to overstate their case, which many believe to be how to persuade people. The online GT basketball community turned into a war of who could explain Hewitt's suckiness was suckier than everyone else. The most effective method they employed was to claim he was a better recruiter than he actually was in order to prove that made him the worst coach ever. They even tried to claim he didn't really coach the 2004 final four team, it was a facade, those players coached themselves. They then started using NBA success of some of his players as proof that he was the worst ever. Any success was spinned into proof of being bad. Any failure was more proof. All things proved it.
Then the revelation of the never ending contract was published in the local paper.
It spiraled into what lingers as the Hewitt hate.