I believe that the premise of a good animation is to have its own unique signature and unique style. Even in some technical improvements and innovations. Not something that is copied exactly and without any technical improvements or innovations, even if it is not as good as the original and does not make sense.
I have a very good example here, Cars and Superfly. The character design shows that the characters are very similar to each other. The overall style is similar and Superfly doesn’t improve on it or even make it more dull. In terms of content, it is plagiarised and stitched together with no idea of its own, and the story is relatively unconvincing and unconventional. Technically, the overall movement is stiff, not copying the essence, not improving or innovating. I don’t think it’s possible to call the animation good in this context.
From my personal point of view, I think a good animation is something like the following, with a well-connected storyline, original content, characters with character and a very imaginative film, which not only reflects the unique French dark humour, but also includes a lot of innovative song and dance elements. The film is also thought-provoking, with a profound philosophy of life and death coming from the mouths of the animated characters.