There is also long-term effects this could have on the franchise. Doctor Who, Star Wars and Ghostbusters were all criticized for their perceived SJW agendas and leftist politics. People complained that those characters were no longer fictional characters that starred in fictional stories, they were appropriated symbols for political agendas. What makes you think that changing Superman's skin color won't cause a backlash or upset the fanbase? The moment you change a fundamental aspect of Superman, that means Superman stops feeling like a real person and just feels like a faceless, impersonal concept that can be changed at an author's whims and subjected to a political agenda. People want their fictional characters to feel like actual, human beings. That's why they are, to varying extents, opposed to change in their identities and attitudes.