Nothing has to objectively be mentioned, what the hell. It's Giant Bomb's GOTY awards. They pick what they want.
And they're not going to mention games only one of them played when that one person hated it. But it's OK to call that a gap in knowledge. Being a Giant Bomb thread there will always be people who can't handle that type of criticism, though. Hell I remember spending many pages arguing with a guy who said it was Sony's fault that none of them knew that digital PS2 games had been for sale on the PS3 for over a year.