This is the one thing a lot of people never realize. Animation takes a long goddamn time to produce and costs a shitload of money needing an army of animators, character artists, background designers, color stylists, storyboarders, cleanup artists, etc as well as the actors, directors, musicians, and then post production effects artists....and it takes around 2-4 years to make on average. The goal will always be to make it have the largest audience appeal as possible. So that means a movie is going to cater primarily to White people in America, Canada, and Europe, and Asians in China.
No one is going to waste their time making a purely black movie for black people only in just one country unless it's a home made project from a team of very dedicated people who do not mind working for years and not being paid for it at all, or a shit level production with all the budget f a tv episode given to it. Even then they run the risk of the target audience not even liking it. American Black people are not a perfect homogeneous block of dedicated consumers, so you are only at best going to get a percentage of them anyway. There is just no profit in it for any studio.