I like Linux a lot, but saying you can’t understand why someone would run Windows on a server just shows a lack of knowledge. Linux is great in a lot of server applications in the application realm. However, it doesn’t get close to the power of Active Directory and Group Policy for Windows device management. Besides that, a lot of people are more comfortable with a UI for managing DHCP, DNA, etc in a SMB environment. Even if they prefer a command line for those tools PowerShell allows those people to coexist with those that prefer a GUI. Under certain circumstances, (mainly ones where a business is forgoing AD for AAD), Linux can be the right choice. Pretending that there’s no place for Windows Server, though, is asinine.