And with Metro onward, Microsoft also has introduced an XML configuration structure as well. Maybe for Joe and Jane Average running Windows 10 Home, as long as they're not interested in anything beyond the sparest kind of modifications that the increasingly simplified and unconfigurable Settings system makes available, Windows remains a simpler system, but for those administering AD domains and the like, it can be an incredibly complex environment. Our recent fun with configuring default applications on domain members, which amounts to configuring a custom XML file to roll out default app changes, shows that things are getting more complicated for any kind of complex administration.
And that's counting on something not going wrong. The printer subsystem in Windows, in my view, has become much more error prone and much less stable than in earlier versions of Windows. Getting rid of old drivers, or in some cases event trying to get rid of phantom printers often involves shutting the Spooler service down, and manually deleting printer entries both from the spooler directory and from the registry, and even then, we've had old phantom connections just spontaneously reappear, even where a member workstation has been moved to an entirely different GPO.
Windows reached a kind of peak of stability and usability with Windows XP and Server 2003. Things weren't perfect, but in general both workstations and servers tended to function in predictable ways that, at worst, you could at least configure around. But even with Server 2008 there were already signs, like IIS configuration nightmares, that stability was no longer a prime objective. Beyond the most basic usage scenarios, Windows can be a nightmare, particularly when things go wrong.