His case was covered in the news, and he still went to federal prison for four years. And every other US telecom CEO knows it.
Another narrative, to my mind equally plausible, is that Nacchio was essentially a crook who got caught up in a wave of corporate crime enforcement in the wake of the Enron scandal for making somewhere between 32MM (Nacchio's experts' take) and 100MM (the USG's take) selling stock he knew, sometimes within days, would be worth a fraction of what he was selling it for.
But die by the sword, perhaps live by the sword: the NSA scandal provides Nacchio's best tool for rehabilitating his image.
I think a read of the case on PACER sort of bears out that narrative. You can just skip to the competing sentencing memoranda (note what Nacchio stipulates to) to get the particulars of what he's charged with, and get a sense for how sweeping the behavior was and how likely it was to have been tied specifically to NSA.
I don't like NSA any more than you do, but I think I like corporate crooks even less.
I mean, that was basically the extent of it though. There has been little-to-no actual systemic change.