This is a myopic view of the concept of race.
Race is defined as "the classification of humans into groups based on physical traits, ancestry, genetics or social relations, or the relations between them. First used to refer to speakers of a common language and then to denote national affiliations, by the 17th century race began to refer to physical (i.e. phenotypical) traits. The term was often used in a general biological taxonomic sense, starting from the 19th century, to denote genetically differentiated human populations defined by phenotype."
Superman and and Jon fall under the category of a separate race by way of physical/phenotypical traits. Phenotypical meaning an organism's observable characteristics or traits, such as its morphology, development, biochemical or physiological properties, phenology, behavior, and products of behavior. In Superman and Jon's case it's biochemical traits, thus they are of another race.
Sure, but then there are people out here who are very much of direct African linage yet they don't have traditional African phenotypical characteristics. Ever heard of Pete Wentz from Fall Out Boy? His granddad is Jamaican. He straightens his hair (nothing wrong with that) and he very much passes for just straight up white. How about Anatole Broyard? He was in fact born to light-skinned black parents, and raised in a predominantly black Brooklyn neighborhood. He looks typically white. What about Wentworth Miller (currently playing Captain Cold on Flash and Legends of Tomorrow). He's mixed with African-American, Jamaican, Jewish, and Cherokee. Michael Fosberg's biological dad is black.POCs are divided by society anyway no matter what kind of background you come from. I can't put on a pair of glasses that I don't actually need to hide I'm African American.
Mixed race people who all pass for white. Doesn't make them any less mixed race. Jon and Superman are aliens that pass for white humans.
If you accept that he only happens to look human and caucasian then you must realize that his other phenotypical characteristics oppose the idea of him simply being a caucasian human. Superman and Jon are totally separate species.Superman is an Alien....a different being from a different planet...who happens to look human and caucasian that's how he is able to function in this world.