I think we long passed the point that higher fidelity, higher texture resolution, and higher polygon count graphics really make any difference anymore to the gaming experience. Nowadays, it seems actual human art-direction, as opposed to raw calculating prowess, is the more important. Also, as someone above pointed out, sometimes the need for higher performing hardware is not because the game engine is really doing anything that spectacular; it's because the developers were so butt-fucking lazy/incompetent about optimizing their algorithms and code. Come to think of it, relying on higher-end hardware to make great looking imagery is also lazy, because you're just trying to calculate your way to pretty pictures rather than having any real artistic skill, aesthetics, or sensibilities (any trained monkey can make a highly detailed, pretty picture, but only an artist can make something that truly moves you).