Pixel art is not just a art style reminiscent of the past, but rather it is a distinct style similar to mosaics and and a form of pointillism.
In its original form, pixel art was a way to produce high-quality artwork within the technical constraints of the hardware it was being displayed on (at the time, mostly constrained consoles or computers such as the PC-98).
Many of the modern artworks being created now use colours outside of a traditional 8-bit or 16-bit (high colour) range, I think this is one of the clear ways the style has evolved.
I have tried to make some of my own with the brilliant pixel art program Asesprite, though my attempts are rather meager compared to others.
One of my favourite things about pixel art is the common usage of restricted colour palettes. Palettes which have a low number of colours or have a pastel feel are my favourite.
Anyway, enough about pixel art in general, and now onto my top artists.
ぺこたぺちか (Pecota Pechka)
Pecota Pechka has two OCs,「黒木」 (‘Kroki’) and 「西園」(‘Nishizono’) who are both a type of「獣耳」 (‘Kemonomimi’) or ‘humans with some animal-like features’ which have features based off of a rabbit. PPechka's work is largely GIFs and small looping animations, there is an emphasis on a fashion aspect as well.
ななみ雪 (Nanami Yuki)
Nanami Yuki often uses pastel colours, with a fixed artwork size due to her using the dotpict program to draw. Dotpict itself is pretty nice, and collates many different artworks on their website or in the app.
Potato Woo does the best food pixel art (at least I think so), she also has a lot of other pixel art surrounding fashion in an ‘anime’ style.