When Microsoft announced the new "Game Mode" coming to Windows 10, consumers actually started to believe that the company was actually still dedicated their promise to make gaming great again with Windows 10. This Game Mode, available starting in the 14997 build of Windows 10, was speculated to do something similar that the Xbox One OS does. It would allocate resources away from non-critical programs and OS processes and put them towards the game you're playing.

Well, it turns out that Microsoft is going to Microsoft and will implement this feature only for their Universal Windows Platform (UWP) games. This absolutely unsurprising verification comes from Windows Central.
I've removed some speculation about Game Mode helping titles like Battlefield 1 achieve a higher resolution on Xbox One. "Game Mode" is specifically a feature for Universal Windows Platform game development for games in the Windows 10 ecosystem, and shouldn't be seen as a "secret sauce" giving the Xbox One a performance boost.