There's a lot of discussion about that in the "classic" pixel art circles. More generally, if you look at it from this angle, pixel art itself is "from the wrong era" of digital art since it is literally self-imposing constraints that maybe used to be there by external imposition but don't need to be anymore.

I've come to the conclusion that whatever we call "pixel art" is just a range of subjective preferences that may be more biased towards aesthetics, or techniques, or tradition, or even "pseudo-tradition". Nowadays the trend seems to be aesthetics with disregard to technique, but there are still many people who consider it "cheating" if you use the "wrong" tools, there are those who want to emulate the exact specs of certain machines, and there are those still who have a mashup of rules that aren't fully justified if not historically (the best example I know is Pixel Joint, but in the end their restrictions have created a community that has flourished and produced awesome art anyway).