Because there is nothing to get besides racism. The very very few edge cases out there where race mattered and was miscast never get mentioned because usually the person who did it wrong says sorry and there is no story. You are giving the enemy too much credit.
And yes I don’t think she was miscast in Annihilation. The second book came out after they started making the movie (which is when that one line about her facial features was put in) and the fact that she had partial Asian ancestry wasn’t plot important in any of the 3 books.