It was moreso marketed as a "for all girls" movie.If their intention was to market this as a black movie imo they failed. I saw the trailer in theatres and it didnt strike me as one at all.
Black Panther, taking place in Wakanda and having source material where people knew what to expect from the jump was much clearer in this. A wrinkle in time seems more like a wizard of oz from the trailer than a movie like black panther.