Yeah, people are stupid and ignorant, aren't they.
This was my thought. it's not like Black Adam is soooooo popular and well known that a significant segment of the population will be mad, it's not like Mary Jane or Lois Lane. They can rename the character (Iris?) or make a new character or have no love interest, or whatever. it's fine. No need to rile the folks up about having a Middle Eastern character named Isis in the movie.
Although if its a movie about ancient times, maybe they won't care.
On the other hand she could be the next Wonder Woman . . . (just not for the American crowd.)