Compare movie posters of women whose eyes or even whole heads you can't see or that are reduced to legs vs. movie posters of male actors to whom this is rarely done and it is clear what is happening.
Top this with the problems people of color face and that the new poster takes away her facial look, the look of a person of color and replaces everything that reminds of her with a bland face that could be anyone and I understand her anger.
She could have explained the issue instead of lashing out, because so many of her fans (and people in ths thread) don't understand the problem and education is necessary and more helpful for everyone.