everyone nostalgic for pixel style Pokémon graphics is looking at the past through rose colored glasses. 50% of the pixel art style used in Pokémon is average at best, with a few charm points. Not bad, but still mid-tier compared to other games, just like now.
Gen V had the best art because Gamefreak opened up more to experimentation. It was weird, but iconic, and the music matched the clashing aesthetics that somehow worked well together.
I don't know if Pokémon should revisit that style for a core title. It might put the normie crowd off, but a high-bit era Pokemon game might be what unites the nostalgiafags with the normies.