i think xyz's complaint is valid, and he's not the first one to make it.
precedent says that format ambiguity is left in the hands of the voters. pixel is essentially visual wildchip; pixel entries don't have to conform to any specific hardware's visual capabilities but they do have to look like "pixel art", whatever that means, just like how wildchip entries do have to sound like "chipmusic", whatever that means.
my suggestion is to use the draw format if you want to be sure that your battle unambiguously permits all sorts of digital (and traditional) art, and to expect voters to draw semi-arbitrary lines of authenticity otherwise.