The issues with capturing images of dark skinned people is due to lower light reflected by dark skin tones. It's the same reason why an f-22 is harder for a radar to pick up than an f-16. To have "dark skin" is, quite literally, to have skin that's more radiation absorbent in the visible spectrum. The "racist" screen unlock works just as bad on dark skinned south Asians. Despite south Asians not exactly being underrepresented in tech. Front facing cameras have a tiny lens and image sensor, that's why a lot of phones started adding a front facing led to illuminate faces that were getting insufficient lighting. Eventually, more advanced techniques like IR cameras and depth sensing light grid arrays made the issue of skin tone irrelevant.

This was a problem due to the fundamentals physics of sensing dark faces. It wasn't limited to Black people, a group that's considerably overrepresented in tech experienced the same issue. And this problem was solved without a big demographic change in the tech companies involved (what is the representation of Black engineers at Huawei and Samsung?). I always get a chuckle when people use this example as justification for DEI policies.