Microsoft broke the wrong compatibility
Windows 8 has backwards compatibility with Windows 7, even though there was a brand new look of live tiles, user interface, and the look and feel of the hardware. Xbox One breaks compatibility with the Xbox 360, significantly reducing the usability of the gaming and media device out of the box.
I wonder if Microsoft would have been in a better position at the end of 2013 if the Xbox One had the compatibility, and Windows 8 didn’t?

Does it make a difference that we might be more adaptable to changing our gaming habits than our work habits?
For instance, I have some expectation that when I pick up a new game I may need to learn a new set of skills to play it successfully. However, if I’m used to working a certain way on a daily basis, it’s incredibly easy to get frustrated if things don’t work like they’ve “always” worked.
So if we’re talking about compatibility, while MS might have been better positioned, I think the outcry against Windows 8 might be even louder if we hadn’t been able to pull through some of our user experience from Windows 7.
I also suspect there’s a different expectation on the gaming side. We want to be wowed, and if backward compatibility lessens the potential wow factor, then it may be in the best long-term interest of Xbox One to break with compatibility.