Comment by martin_ky

That might be the original motivation, but post-7 Windows UI is anything but unified or consistent. New and legacy UI toolkits are mixed in the system shell itself. There are still parts of the good old Control Panel that haven’t been ported to the new “immersive settings” app. Already in a clean Win 10 installation, you can spot at least 3 different styles of context menu, depending on which part of the desktop you right-click.