I don't entirely disagree with you, I get what you're saying.

But I definitely don't see Windows as being tightly focussed nor a single predictable entity. The differences, nuances, and upgrade paths between 95, 98, ME, XP, Vista, 7, 8 are as fragmented and confusing as possible.

Linux isn't any better, this is true. But I don't buy that it's because of singular vision that Microsoft continues to dominate. Today Apple has the strongest composed experience, in my opinion. Too bad they have basically zero corporate presence.