hamilton is a comedy/musical, and is not supposed to be in "canon" or "continuity" with actual reality. What is cursed child based on, not reality, but the books. Is it supposed to really be a sequel and in continuity? It's marketed as such. Well sometimes writers make mistakes and things don't fit continuity but it's a legit criticism when they don't do it by mistake but on purpose. Seems to be done for virtue woke points which is pandering. The characters in harry potter were almost all white. Now what if this sequel took the minor character dean thomas, a black boy who went to hogwarts, and expanded on him, maybe showed his story more, showed how as an adult he became a great wizard etc. Or Kingsley Shacklebolt. A good character with not much explained. People don't like blackwashing for same reason they don't white washing. It's really bo different than blackface. Maybe "not as bad" with fictional characters but still a slap in the face to fans.