Is anyone naive enough to believe that if bill gates didn't end up crushing the competition as he did during Microsoft's rise, some one else would not have done so ? Sure, we may/may not have Microsoft as powerful, but there would have been some other draconian-soft to fill the void.
And though we should probably not pull Jobs in to this, if we are to imagine Jobs at the head of Microsoft when it is in a position to crush competition, I can't imagine Jobs (and many other business leaders) deciding otherwise (going by the current set of apple law suits). It's just like the lord of the rings - doesn't matter who wears the ring. The heady power of the monopoly is just like the ring (the governmental laws for fair competition should be such a way that they never form). If monopolies do form, there is no point blaming individuals for that.