Q. How should I manage Windows 10, using Group Policy or Mobile Device Management?
A. With Windows 10 Microsoft standardized the OS across all platforms including desktops, phones, HoloLens, Surface Hub, IoT devices and even Xbox. As part of this the Mobile Device Management (MDM) platform is now part of the Windows 10 platform meaning it can be used in Windows 10 desktop such as Pro and Enterprise.
Windows 10 actually standardizes management through the use of a Common Device Configurator that is utilized by all the management platforms which then uses MDM Configuration Service Providers (CSP) to light up configuration options. A WMI Bridge exists to enable tools like Configuration Manager to use the MDM CSPs.
When choosing whether to use group policy and standard desktop management solutions like System Center Configuration Manager or a Mobile Device Management solution like Intune really depends on how you use AD vs Azure AD.
If machines are AD joined then you will utilize Group Policy and tools like SCCM.
If machines are Azure AD joined or use Azure AD identities to logon then you will use MDM solutions.