It's probably more due to it being very obvious pandering and diversity quotas. We know it's not done for the character. We know it's not done because it makes sense. We know it's not done because that's how it would actually be.... otherwise, the cartoon would have established a diverse culture.

It's been shoehorned so much that it's become a glaring red flag. X# of characters have to be this, X# of characters have to be that. What's even worse is that maybe she is a good actor. Maybe she did deserve that role... but because so many other characters have been changed for diversity, she is also automatically flagged as a diversity change. Whether it was meant that way or not.

Hollywood or whoever is making movies these days do not know how to deal with diversity of people or culture. They do not know how to deal with presenting a "melting pot," peoples, but they still try to throw in a character that is very different from the rest of the characters, like its normal.

An all white tribe is on an island of dragons.... where did the one black chick come from? Was she adopted from another culture? Was she taken in a raid? It's a whole other story that won't at all be mentioned or explored since she is just a skin color change.

Humans are quite tribal, so even if we have no problem with people who are different from us, we still notice when people are different and ask questions.