No, not really. There is still lots of room for improvement, especially if you want high resolution (retina or large display), 3D, multi-monitor configuration, and/or high levels of anti-aliasing. And providing stable 60FPS on 1080p can be difficult if you have mid-end or couple of generations old hardware.
Those gamers that demand 1080p@60Hz under load are a niche, not the standard for 'pc gamers'. And for those who demand it, shelling out a few extra dollars for hardware that exists (previously it didn't) is much easier than messing around with hardware voltages and crossing your fingers that your gpu is one of the lucky ones.
And frankly, the idea that gamers will flock en masse to linux for a few FPS is utterly absurd.