Why isn't someone grabbing the chance to take a linux distro and polish it to get that audience? I would happily pay for that OS so I can use it with any PC/laptop I want.
So who is going to ensure a smooth experience when it should support any PC or laptop? Either you have the marketshare of Microsoft and have device vendors care (somewhat) or you can only guarantee a good experience for a relatively small set of hardware (as Apple does).