If you think it's a bad experience when you have a single OS (plus first-party apps) vendor, and a separate manufacturer (e.g.: my Lenovo and it's bevy of task-tray items), try it now with two fully supported OSs out of the box.
While I agree that it sucks that Google and Microsoft both are trying to defeat this initiative, I can also say with a 95% certainty that even if the both condoned it, it would still be a really bad experience.
Google's hypocrisy with android being "Open" is what's really exposed here - in honesty, both Microsoft and Google are as bad as Apple in desiring closed platforms. It's just that Apple seems better at delivering said platform.