The early days cameras were less sensitive to red light needed for darker skin tones. Some of this could be overcome with lighting that wasn’t readily available. It possible to do it sure, you could make a picture that was close to the clarity of lighter skin tone. If you have to put in a lot of extra effort and time (that often wasn’t done at all) to take the same picture you could of a white person, I’d say that means the film doesn’t work well with black people. It clearly wasn’t particle because people rarely put in the effort to properly light them. Why argue with something we have facts about? I didn’t make this up in a shower. I read it in articles written by professionals.