Some of that has to do with the fact that games back then hired professional artists, many of whom who had often never worked on a game before - compared to today, when the only people making pixel art games are zero-budget indies often hiring literal teenagers with no professional art background at all.
But the biggest part is they are using "pixel art" as a crutch to make very lazy, no effort graphics. The same as "CalArts" is for cartoons, or the "tumblr nose" for webcomics.
There exists no reason other than pure incompetence (and I'm talking the lack of trying kind) to have characters with less detail than Mario whose entire game was 40KB.
And that's not even just an SJW thing. Look at pixel games from back in the day and compare it to most pixel artists now.
Some of that has to do with the fact that games back then hired professional artists, many of whom who had often never worked on a game before - compared to today, when the only people making pixel art games are zero-budget indies often hiring literal teenagers with no professional art background at all.
But the biggest part is they are using "pixel art" as a crutch to make very lazy, no effort graphics. The same as "CalArts" is for cartoons, or the "tumblr nose" for webcomics.
There exists no reason other than pure incompetence (and I'm talking the lack of trying kind) to have characters with less detail than Mario whose entire game was 40KB.
Metal slug and other snk games still look amazing