Well there is a kal-el who is black from earth-d,and that happen in comics before val-zod and the other black supermen.
Kal-El (Earth-D) | DC Database | FANDOM powered by Wikia
Superman is the greatest hero on Earth-D. With his wife, Supergirl, he is a leading member of the Justice Alliance of America.
https://dc.fandom.com/wiki/Kal-El_(Earth-D)
Maybe they are talking about kalel(calvin ellis) and not kal-el(clark kent).
The one michael b. jordan said he wanted play was calvin ellis but alot folks don't realize that it is still not clark kent but their kryptonian names are the same but written differently.
That could be the confusion.
Kalel (Earth 23)
President Superman
Kalel is the Superman of Earth 23. In his civilian identity, he is Calvin Ellis, President of the United States of America.
https://dc.fandom.com/wiki/Kalel_(Earth_23)
Student Of The Game Podcast Tavares E quote-
Calvin Ellis name is Kalel. Clark Kent is Kal-El. I think the author of the article probably assumed that both names are written the same.