>>974 (OP)
To be a GOAT anime, it has to capture the distilled essence of what anime can be. My kneejerk reaction would be to say Akira, but the cyberpunk setting is too limiting. It definitely has the best animation, though.
Maybe… FLCL? I can’t think of anything else that really nails that immutably ‘japanese’ feel that it does. It’s not the BEST anime, but it’s the most ‘anime’ anime.