The reason we had pixel art in the first place is that's what screens could display. Then, we got super-high resolution displays and the need for pixels went away. I can't even see the pixels on my LCD screen even though it's a foot away from my face right now. So why are they clinging to this outdated concept?
Because something in the artsy fartsy mind takes great delight in "we can do it much better now, but we're going to deliberately use the outdated method instead!" People don't understand why the graphics are blocky and give low ratings. Cue the anguished whining that people just don't understand great artists, smelly unwashed commoners don't deserve the kind of great art that we offer, etc., I think all of us know the rest of it from here by heart because we've heard it so many times.
It's not their fault for making crappy-looking graphics, it's everyone else's fault for failing to recognize artistic brilliance when we see it. If it IS popular, then it's bad art by definition (Leland D Howard, Norman Rockwell, etc.)