Starting with Windows 10 build number 15042, Microsoft will allow administrators to block the installation of Win32 applications on their computer. The feature will be available for all Windows 10 editions and will come with a corresponding configuration option in the Windows 10 Apps & Features settings screen. The advantage of this Win32 app blocking feature is its security implications. Unsandboxed Win32 apps are the main source of viruses and malware on Windows 10. Microsoft still sees Windows’ future in UWP apps, since they work in their own, self-contained security sandbox.
Source: https://www.bleepingcomputer.com/news/microsoft/upcoming-windows-10-feature-lets-users-block-installation-of-win32-apps/