> Unity exists because every other Linux GUI has 
  > fallen victim to this process

That's very debatable. According to me, Gnome 2.3 is by far the best designed UX for a desktop operating system. Like most people, I generalize based on my own limited experience, and I have seen people grow up and learn how to use a computer in Gnome who were disgusted by Windows and OSX user interfaces. Like all animals, humans can be conditioned and there's simply no such thing as "best UX for all".

Lets look at Alt+Tab functionality, which now in Unity (and Gnome3) switches between "apps" instead of windows. The problem with Unity/Gnome3 is that they're doing exactly what Shuttleworth claims to avoid. Quoting Mark:

  > we're not that interested in matching functionality
  > that was in Win95, especially if we think that 
  > functionality will get dropped in Windows 8 or 9 or 10.

Unity (and Gnome3) are both busy copying obsolete UI concepts from OSX, which itself is stuck in the 80s. I would say that they'd be better off copying Win95 instead, at least Microsoft recognized (correctly) back then that a concept of an "app" makes no sense on a modern desktop, and windows is what users want to manage, not "apps".

Mr. Shuttleworth admits to be heavily influenced by Android and iOS. That's weird to me, since desktops are ultimately very different beasts. The concept of an "app" came back from the grave only because the 1st generation of mobile devices were very weak, DOS-like if you will, at multi-tasking and IPC. So... Mr. Shuttleworth picked the wrong corpse to invigorate.

In their mindless pursuit of copying everything from OSX they didn't even bother recognizing OSX own bugs like broken virtual desktops. See, Apple themselves failed to copy them properly from Unix UIs (windows from different desktops in OSX are mistakenly combined in the same useless giant Alt+tab list). But the thing about Apple, though, is that they can afford to have an obsolete window management circa 1985 because their windows are shiny and fly around without lag, while Unity just recently learned how to scroll text smoothly.

In the end, Mr. Shuttleworth really shouldn't mention Win95 at all, which now seems to emerge as a clearly superior desktop UX of all 3, nearly 20 years after its introduction.