The linked article described in detail what many have known. Windows RT, which is designed for tablets is not Windows 8 compatible. It runs only on ARM processors and cannot run any software written exclusively for Windows 8 or any earlier version of Windows.
So please someone explain, why they force desktop users to run Metro? It would make some sense for them technically if RT & 8 were code compatible so they'd only had to support one OS. But they are distinct and there is zero reason to have forced Metro on Windows 8 users.
Whether they can succeed in breaking the tablet market is one question. Whether they have launched another ME or Vista for desktops is another.