This is so completely wrong it's not funny. The majority of Microsoft's server GUIs are now built completely on PowerShell. This includes basic products like IIS, Exchange, etc. Where I work, most consultants who implement or maintain these products have learned PowerShell and use it regularly. Windows Server 2012's default option is "headless" install (Powershell only), and that's been an option since at least Server 08 R2. Powershell is certainly not an afterthought - it is at the core of Microsoft's server administration GUI plans. MS have completely committed to it.