That's to be able to claim an 'installed base of 100's of millions of users' for technology 'x'. Even if none of those people installed it voluntarily or has ever used it.
In their conference they presented that shit part of their VR strategy or similar completely insane BS.
In the same vein, I don't know what they intent to mean by their AI division (esp as a platform, service, whatever) and probably neither do they, but hey, you got to make the speech of the boss somehow vaguely believable, even if the whole earth know it is just for show.
This morning I noticed I have a 3D Objects folder pinned to the This PC item that I can't remove. I also have Mixed Reality Portal and Mixed Reality Viewer that I can't remove.
Why on earth are those apps part of the default install? Worse though - why doesn't Microsoft make it easy to uninstall them? I don't want their crappy news, weather, contacts, maps, music, and other default apps. They should make the apps so good users want them, not force install them and make them uninstallable.