To be honest, if you weren't using the enterprise version of both OS' then I can see why you would have issues. The only true Windows version is enterprise.
You can't claim superior capability of only 2 of the 8 OS's they've made since 2000 and then discount an user experience as a whoopsie. One experience was with a leading computer manufacturer at the time. The other was made by Microsoft itself. Also, Vista and ME were pure crap and inoperable.
I'm not a fan of the use of market share to claim superiority. The only place market share matters is wall street and meeting rooms. Theres too many reasons why a product gains as much of the market as it does. Price point and profitability have little to do with consumer experience. Sure they have more devices running their software in more places. Sometimes it's all someone could afford. Other times it's the only thing offered. I'm not a developer and neither are the vast majority of their consumers, so why should we care about anything other than what we experience?
The university I work for went to surface tablets purely for compatibility with new software. We had what we wanted (the iPads), and our department heads chose for us what we needed based on developers of a specific software. What it boiled down to was money. It was cheaper to buy this software and upgrade our equipment than it was to go with a company that developed for iOS, OS X and Windows.
I can't tell anyone for certain which is over all better. But what I can say is that I've seen little good come from Microsoft, and a whole lot of good from Apple.
XP and 7 best ever - that is probably why Microsoft has to release 7-15 updates EVERY month to fix software errors and security issues.
This is why I can't play Xbox. I play for a few hours a month, but have boo-coodles of updates to install that takes forever. Gaming is totally a different beast though.
I agree with snowmoon that they are shoehorning old devices. It's holding back the potential of new devices, too.