I think what separates him from most of the other elite cover corners is that he shadowed the team's best receiver. There are some great corners who stuck to one side of the field so QBs just threw to the other side. With Revis, he didn't take a side out, but he took the best receiver on the team out. Forcing the QB to throw to everyone but their best receiver is impressive.
Another factor are the rule changes. He played in an era where it's tougher to cover WRs because of all the rule changes.
I don't disagree that if QBs took more shots, maybe he's not as dominant as he seemed, b