Look at this roster: https://i.redd.it/h1alpb7qnj251.jpg
You got black people, native american people, white people, asians, middle eastern people, green people, blue people, big teethed people, insect people, all without masks.
I think it was because the guy who was Johnny Cage was also the model for scorpion, sub zero and reptile, the only masked characters in the original game.