Basically Tyson wasn`t at his best in `96 but was in better condition and more focused than he was in `89, Tyson was dreadful in their first fight his mind was all over the place after he sacked Rooney his body had lost it`s vim, in the second fight Bruno realised this and panicked, Bruno had just beaten McCall and was still at his peak, different level of fighters.
No version of Bruno survives that combination to be honest, Bruno just didn't have the chin to survive Tyson.
Bruno would lose to Tyson at any stage of their respective careers except for the Tyson near the very end of his. But then if Danny Williams and Kevin McBride could beat Tyson by that point, it doesn't really mean much.