A few things come to mind here.

1. MS tried to ship a renegade JDK with proprietary features, back in the 90's. That didn't go very well for them, as they drew the ire of Sun Microsystems which was a decently sized player at the time. It was a clear licensing issue, and they lost the case. Point being: they're historically not great at this kind of thing.
2. The GPL is designed to thwart this scenario, specifically for things like paid software (e.g. Windows). MS would have to move to a "free Windows software, paid service" model before any of this could happen. But the service must be optional, and they'd have to provide the source to anyone that wants it. That said, they're on track to make Windows free (as in beer), so who knows?
3. Nvidia gets to ship binary Linux drivers, so closed-source binary packages for MS proprietary components on top of Linux might be possible. But again, I don't think they get to charge for that.
4. WRT to drivers/packages, RedHat famously charges for access to their package repository, making automated patching and upgrading a nightmare if you go without. This is one hell of a GPL loophole and worthy of far more corporate exploitation. I can easily see MS following this path.
5. "The net treats censorship as a defect and routes around it." - John Gilmore - (Many) People will just fork away or happily sit somewhere else in the GNU family tree, far from anything MS builds. If the need arises, compatibility layers like WINE will show up eventually.