That isn't a real argument.
Even if Crysis2 is PC exclusive they still have to cater for middle lower end PCs, older shader models, direct X 9 and all that.
Games uses graphic options to micro adjust performance for different hardware, and its no different for consoles. You can dish out the same game with fewer shaders, lower resolution and less detailed textures, it won't limit how detailed it is going to be in full detail.