Because they are complaining about factors that an Open Source approach would mitigate, like development resources and targeting features that make the most money as opposed to what benefits the community.

If Windows was Open Source, this would have been addressed a long time ago as this feature is desirable to what one would consider a power user. Advanced users are also the ones who roll up their sleeves and will fix a problem if they can, especially if no one from the parent company is making any effort to do so. But, thanks to Closed Source protectionism, they can't. And because their value to Microsoft is the same as any other user as they pay the same license fees as anyone else, the voice of the power user is drowned out and their concerns are never addressed.

This is just one glowing example of Closed Source working against the betterment of a platform.

Seriously, how can one NOT reach the same conclusion?