Red Dead Redemption would disagree with that
So would Just Cause 2. With both phenomenal console and PC versions. The PC version was built from the ground up for DX10, runs HDR,dynamic shadows, SSAO,large view distances, physics, GPU calculated water simulation (on Nvidia), God rays etc. And it runs on my laptops Geforce GTX460m...bought for a desktop that card is $120.
See the its important the PC version supports modern features because of things like what Just Cause 2 does. I'm also playing Risen on PC, its DX9 based, but has horrid performance in comparison. Some of this is to be laid at the programers feet but also much of it is due to using an outdated inefficient Api like DX9.