You raise the point that should come to everyone's mind as soon as they read that article. Ability to perform well on supercomputers and ability to perform well

You raise the point that should come to everyone's mind as soon as they read that article. Ability to perform well on supercomputers and ability to perform well on desktops or laptops are not necessarily related. As for Linux not having a standard GUI, "Linux" and Windows are not really directly comparable. I could say that win32 doesn't have a consistent GUI, since it's been used on multiple Windows operating systems. Linux is a building block, not the whole package. Windows is a whole package. Let's compare apples and apples.