Graphic designers in marketing > UX specialists
I think the idea of putting fault to UX-designers (or computer people in general) is wrong and the actual problem is that user interface is designed by graphic designers in the marketing who have absolutely no idea of how user interface should be made. And they don't care at all.
People who see user interface as a piece of paper and usability is a word that doesn't even exist: They want just "clean" looks and that's that. That's what the graphic design is about.
So marketing opinion ("looks") trumps knowledge, basically. Is anyone suprised?
"Microsoft MUST have done something that showed the same effect in the new Windows UI, they test a lot and would inevitably have caught this amount of difference. And went ahead with it anyway."
Exactly that as marketing decided, not those people who actually know (UX designers). Yet another stupid decision in a long chain of them within Microsoft.
But not only in MS, it's a larger trend that marketing is overpowering the IT and that causes huge amount of totally stupid designs everywhere as marketing has no idea about functionality, they see only looks and nothing beyond that.