Damn, here's my conflict of interest:
1. Carmack's a smart guy who's been doing this for a long time (and obviously knows what he's doing).
2. He makes this statement right after his company provides a piss-poor port that makes it seem like he's using it as a justification.
3. His previous statement was the reverse of this.
I'm leaning towards 2, but I do agree that PC sales don't make up a large sum of triple-A titles. However, that's no excuse for failing to provide proper play-testing and decent port development (not being able to change ANY of your graphic settings? That's just lazy).
Despite the fact that its sales are lower, the PC remains an important gaming platform. It provides an excellent venue for independent developers and people starting out, and also typically offers up cheaper games, despite the hardware being more expensive. Typically I've found the communities for games to be a bit better as well, and the creation of mods just allows for a much more expanded and longer experience. I've also found that PC games are often more experimental then console games as well, but that's just me.
I really don't see why everyone has to turn this into an immature 'us vs. them' pissing contest that makes everyone look like idiots. Let's just demonize the shit out of each other, right guys? "Oh, those PC gamer elitist pricks are so annoying!" "Man, those console retards just don't know what they're talking about." Please, this is just such a tired, dull argument over something so pointless as personal taste. All I want is decent development and some customer respect across all platforms. My PC's my wife, but my 360 is my mistress.