It can be categorized in so far, that one system of categories doesn't exclude the others. When talking about pixel art, it can be useful to refer to a system that better suits the point you are trying to communicate, since the collective categories of one system represent an idea different than the collective categories of another system, providing context. Seen like this, it is possible to create a formal collection of systems and attitudes in pixel art, each made concisely different in its categorical approach.
So it doesn't exclude through bias, it includes all forms of bias. Rather it is the lack of a formal history of pixel art that creates pixel extremism, unaware of the great variety pixel art has always had, and that it can be different tomorrow, since it has been evidently pretty different yesterday. Pixel art does not get technically tainted, technology gets pixel painted, like by a bunch of graffity sprayers roaming the e-'hood at night.
"The pixel boys were here! your shiny new screens ain't save from pixel power, yo. Eat it, suckers."
A bit more elaboration on how unlikely factors shape motivations on pixel art style:
I believe that the renaissance of "retro" graphics in games happened primarily because of the harsh reality of development today. Childhood nostalgia is not the reason but the marketing spin on why lesser quality of content would be better for the consumer, when it really serves the developer first. So it's tempting to say you might as well call that category "Indy dev".
Production of assets for modern games has become so overly intense and costly -- risky -- that it hinders the spontaneity in creativity. You need a dozen specialists these days to see an asset through the pipeline. The industry is in a vicious cycle of a higher and higher fidelity race that fewer and fewer can compete with, resulting in stale sequels of a hand full blockbusters.
So doing really rough retro graphics, almost down to the symbolic level, enables very few devs with simple means to create massive amounts of content, and concentrate on fresh and finely tuned game play. Look how much fun Mathias has lately with that little animated guy, his creative focus shifted, he can pump dozens of cool animations. Or Bitslap with his little dudes.
That is to say a motivation behind a style can be efficient productivity of the artist. Maybe also see Mrmo's blocky/tiled pixeling style.
To be honest, it is a bit ironic to see the fidelity arms race spilled over to Pixel Art production, so that its greatest strength is lost as far as games development is concerned.
Merged posts - Crow