Re: Skin tone is not binary with the meta groups
Probably a bit of both.
Computers are less good at recognising that black people actually have faces. That is due to the way cameras have been optimised to pick up lighter skin tones.
Also, secondary sexual characteristics interact with racial differences to make it difficult to gender people across different races.
One example is shape of forehead. If you look at white people, women tend to have a more vertical forehead and a low hairline, men tend to have a more diagonally sloped forehead, a more pronounced ridge above their eyes, and a higher hairline.
These differences also appear in black people, however black people tend have a more diagonally sloped forehead and higher hairline than white people, so you might find more black women with a similar shaped forehead to white men.
Also, black people are far more genetically diverse than other groups, so you can't make the same generalisations about them. There could potentially be more difference in DNA between one black person and another black person, than there is between one of those black people and a white person.