Again with the biracials portraying full black people?

I just watched the first episode and the whole time I'm wondering is Grace the mother's daughter and not the father's... but then I see the dynamic between her and the father and I'm like okay... so maybe she's the father's daughter and not the mother's because clearly she's biracial. Towards the end of the episode I sadly realized that there probably is no backstory (someone please correct me if I'm wrong!!) and they just have this half-black half-asian woman portraying a racially black character.

This type of casting with biracial black people filling in for American black people (black people with, on average, about 80% African ancestry and 20% European ancestry) is confusing, annoying, and offensive. Merle Dandridge couldn't portray an Asian woman, but they're still going by the racist one drop rule to allow someone who looks like she has less than 50% African ancestry to portray a black women who's supposed to have about 80% African ancestry. She may be "black" ethnically, but she isn't black racially. She's biracial, and she looks it.

One incident is excusable but when it happens over and over again it's a problem. It's not good for black people's self esteem. Just the other day Simon Biles said she wanted Zendaya to portray her in a biopic - ZENDAYA.
Not Quvenzhane Wallis.
Not Keke Palmer.
Not Imani Hakim.
Not Rhyon Nicole Brown.
...I would be surprised if she even knew their names.

Look at this list of "Young Black Actors and Actresses" on imdb and look at who's at the very top of the list: Zendaya, Roshon Fegan, and Amandla Stenberg - all biracial and lighter than sand. http://www.imdb.com/list/ls055620113/