The people behind this movie do something that Sakurai couldn't do to Sonic in Smash Ultimate - give him realistic fur.
I really like the design, I know I'm probably in the minority here but movie Sonic is well-designed. I had wanted all the non-human mammals in SSBU to be designed with realistic fur textures, but four of them didn't get that treatment - in addition to Sonic, neither Isabelle, nor Pikachu or Pichu got realistic fur in SSBU - though filmmakers did give it to Pikachu for the Detective Pikachu movie.
I really like the design, I know I'm probably in the minority here but movie Sonic is well-designed. I had wanted all the non-human mammals in SSBU to be designed with realistic fur textures, but four of them didn't get that treatment - in addition to Sonic, neither Isabelle, nor Pikachu or Pichu got realistic fur in SSBU - though filmmakers did give it to Pikachu for the Detective Pikachu movie.