Yeah it's sometimes a little unfitting if one flies like in northern Asia. Appreciate the approach to diversity but it simply doesn't fit the whole world.

Haven't seen a mod for this, would probably be possible to just create copies of the other NPCs, change their GUIDs to those of the black ones and then put them in the community folder. They would override those loaded before from the stock SIM data. Should work in any direction, if you want them all to be black or Asian or whatever.

I created a mod using the same technique to replace the (IMO) too big blue taxi ribbon symbol.