Well, if you believe Steams survey from Janurary 2013, a combined 72.3% of users have at least a DX10 capable video card with a capable OS.
21.77% have a capable GPU, but not a supported OS.
While steam doesn't account for Every PC gamer, I'd imagine across the board of PC gamers, the numbers are still above 60% for DX10+ capable systems with supported OS.
So while you could still argue there's a good portion holding gaming back, you could also argue, they may not find a need to upgrade to DX10+ because nobody uses it hardly, least not truly supports it, since primarily the console market seems to now drive gaming, and they don't use DX10+, so why dump money into something that isn't yet used?
Not every gamer, as we all know, can just drop money to future proof themselves, there has to be a need to do it, with DX11 GPU's coming in the new console generation, perhaps that need will arrive in a few years.
But the system itself is ever decreasing in the amount of how much it holds PC gamers back, mostly it's developers now, which means the console hardware is the problem more and more.
[citation][nom]wedouglas[/nom]Of all the PC gamers, how many have latest generation video cards? A fraction of them. Unless every PC gamer upgrades to the latest and greatest every year, you'll never see games taking total advantage of your video card.[/citation]