I entered Zlatan's mind yesterday, as you obviously did too, and I saw the same things you're saying now.
For whichever reason it was, and we can't know what it was, he actually dared to publicly shove it to Inter and the Inter fans by saying that the scudetti were won fair and square and not only that, but he also said that his Juve was stronger than his Inter (and his Juve was apparently cheating it's way to the titles, according to Inter).
By saying that his Juve was stronger than his Inter, he was again saying that Juve's team was winning because it was strong, not because it was cheating.
At the same time Zambrotta was saying how he feels betrayed by Juve. Betrayed in what way? We betrayed him because we cheated?
Face it, Zlatan was saying all the things that Juventini were saying and thinking, but unlike the Juventini, he was saying that from inside Inter's camp, from where it hurt them the most.
Even if he did it for selfish reasons, he at least did it, unlike anyone else outside Juventus.