The SMS and C64 were 8 bit systems, though too, solidly from the same generation as the NES. They don't strongly outclass the NES, just enough that the music is more enjoyable.
Compare Skate or Die on NES to the C64 version - the title song is so much more rockin'. Or any NES RPG to Phantasy Star or Ys for the SMS... the difference is profound.
