It depends who is singing the rap. I remember that there were some protests about the rapper “Eminem” getting some music award. But “Eminem” is a rare white rapper. I think it’s ok to criticize rap if you criticize Eminem. But, you are now allowed to criticize black rappers, because that would be racist.
Sorry, meant to say “NOT” allowed to criticize black rappers, not “NOW” allowed to criticize black rappers.