I know one person in my immediate sphere who has vitiligo, and she's a white woman. I have never in my life met a nigger with it, and I run in some pretty multicultural circles in a multicultural location.
Though no one seems to look at the statistics of who it affects because last I checked, it affected Hispanics and Asians the most at nearly a 0.30% prevalence, or something along those lines. Blacks have like a 0.20% prevalence. Whites are less common, somewhere along a 0.15% prevalence.
Overall though, it is fetishism for an "exotic" skin disease that is actually quite terrible to have. The condition itself includes hearing loss, sight loss, hair loss, it can even fuck up the mucous lining of your mouth and nose. Not to mention atrophy of the skin affected by the loss of melanin. It's also a co-morbid disease, so if you have vitiligo, you usually have something else severely wrong with your immune system and it's responses. (Usually a genetic defeat, diabetes, severe anemia, etc.) You can sometimes get it from working around certain chemicals or from having a stressor event, but that's rarer.
It's just a big, bright, glaring red flag for "This person is unhealthy and has multiple diseases." on so many levels. DEI Wokescolds don't care though. It's all about the progressive check marks and uglification of media.