Part of the problem is that there was a tutor tha fed the media beast for several years. She claimed she did academic research and found football players were writing at 4th-grade levels and that four-line paragraphs were turned in as final essays. She was the beating heart of the outrage. Turned out she was making up her work while also pushing a business venture and a book deal. No one who investigated could find anything approximating what she was sharing, and she dropped off the radar even while the media narrative she framed stayed intact.
Unable to find evidence for her allegations, the NCAA was left trying to decide if the -Am department was substandard academically, something they are wholesale unqualified for. Opting to skip the part where they decide to tell a university how to be a university, they had the impermissible benefit card. Which is a huge card (UNC once got dinged when a player spent two nights on a couch). But it also is a difficult one to pull off when you ignored similar cases at Michigan and Auburn. Incidentally the NCAA allows athletic departments to run college credit courses available only to athletes. Walking that tightrope between those two mine fields would have been possible but also could have been appealed and litigated. I'm assuming the NCAA wants to save its war chest for AAU-maggedon.