But are you honestly arguing for forced obsolescence here? The most agile app developers would have a chance at a quick buck. The Windows team could kick out ugly code. And then?
I'm not advocating that the API is cleaned out merely on the technical level, I'm advocating (with a lack of clarity on my behalf) that Microsoft needs to encourage an ecosystem of development creativity. Instead, we get a UI that is abstractly "optimized" for usage but is far removed from providing a pleasant experience for their users.
And isn't Metro exactly what you want?
At best what they've done since Windows XP is change the rat maze for their users by forcing them into a different cognitive "map" of how their PC is to function (ever try using the ironically named "ribbon" in Office?).