No kernel has ever had such a gigantic mind share and adaptability as Linux. Very few tasks demand so much of different areas of an operating system as games. The moment game developers, especially the ones who deeply optimize engines, start contributing and tuning Linux to get as much performance, throughput and low latency as possible will be the moment when games will improve in ways that current option can't compete or offer anything close.
If any of the big vendors of AAA is reading this, please consider that there is a severely under served community who is willing to collaborate, help and improve everything that is needed to make your product run better. Consider that your company would have the power to tune the environment in ways that the competition can't even dream of. Consider what we did to servers, mobile and HPC and enable us to do just the same with games.