From a young age, black kids are told their natural hair is unkempt, and often by white teachers. The view of what is neat hair, and isn’t neat hair is very subjective. This constant unconscious, and sometimes conscious bias is not helpful. It’s often used as disguised form of discrimination.
I’m not saying this is the case with the original poster and think it was a genuine mistake, but it’s something we probably need to move away from.