While I'm sure Piracy is an issue, singling it out as the culprit for low sales is a cop out for a poor design decision.
Crytek wanted to make the coolest looking game they could imagine and said screw the requirements they don't matter... but they do!
I loved FarCry, I desperately wanted to play this game, I still do, but I'm not going to go fork out much more money on PC hardware than a console costs just to play 1 game. I have alot of gamer friends, and not 1 of them bought the game because they new their rigs couldn't play it. Of course everybody got CoD4 because they could play and new it would be great.
I was a PC gaming fanatic and generally despised the consoles. Now as much at it pains me to say, I'm a console fan. The fact that I could buy a 360 that will play any game at it's full quality for 5 years was too hard to turn down. No more forking out loads of money on hardware every year or 2 to keep up. No more turning down my settings so my graphics look a generation behind what they could. On a console you get the best that you possibly can with that hardware, period.
Piracy does hurt PC games, but I think it's a stretch to put the blame on that for Crysis sales.