Microsoft is going toward a subscription model for Windows, instead of a one-time license fee. This is why every of their products require you to assign it to your Live account; so that, when you buy a new computer, you login in with that Live account and all your software gets installed automatically for you. It also allows then to disable any fraudulent account altogether to invalidate any illegal use of their products.
Also, I do not completely agree with you that VR is the future. It is certainly cool, but it is only but a fad that will be replaced by far better technologies later on, for example holograms and immersive environments like AR. Augmented Reality is not Virtual Reality.
A few years ago, many believe that PC gaming would die due to the ever growing capabilities of consoles. It ain't true anymore, and PC gaming gain so much that consoles as we know it will become obsolete in the future. PCs will become ever more modular and unified, and you can already see this happening with Steam machines... which, by the way, runs on Linux. So, I am not sure that Microsoft Windows will continue to be dominant that much... Even DX12 is threatened by OpenGL Next (Vulkan), which is cross-platform.
The bottom line is, there are many benefits for game studios to start supporting Linux for the games.... there is a big market that will not be moving to Windows when Windows 7/8 reach end of life (i.e. China).
Just saying