1) NCAA had the least bit of reason to act with PSU than any other case. They came down so hard on PSU because they could get away with it due to the utter hatefulness of what Sandusky was doing.

However, this was much more of a legal, criminal action than a NCAA action. Sandusky was a morally reprehensible and criminal act.

2) The NCAA later backed off a lot of the harsh penalties.

UNCheat, Miami and Loserville have much more to do with what the NCAA is supposed to be enforcing, level playing field. It has to do with rogue schools paying players, keeping players eligible by giving them sham grades, and recruiting players by giving then all kinds of illegal (per NCAA rules) stuff.