Thankfully we have some amazing SF writers changing that. Nnedi Okorafor comes to mind, although I find her comics work better than her prose. I have Tade Thompson's "Rosewater" on my tbr pile right now. I also very much enjoyed Rivers Solomon's generation ship novel "An Unkindness of Ghosts."

I also try to at least make sure Black characters are present in my own work. I can't tell their stories like they can, but I can at least not whitewash the future ;).