Would it genuinely kill Netflix to find an actor in Tunisia to play the part? It's not like they have to worry about selling tickets at theaters to recuperate a loss if they don't get enough viewers. They're a streaming service. Aside from maybe Barbarians (only the first season of which was good), the production values for all of their "historical" shows are garbage quality anyway. The mere fact that Denzel would be in one of their shows isn't really going to help them out that much or significantly more than having like five to ten smaller budget shows that appeal to other audiences who would then pay for the monthly streaming service. It's just a needless decision and clearly in the model of blackwashing historical figures like they did with the Greek Cleopatra (now the Phoenician/Carthaginian Hannibal). Netflix seems to be squarely against the notion that various parts of Africa were ever colonized by West Asians and Europeans in its long history, or they're doing this to generate hate views and hate reviews for producing more buzz in general.
"There is no such thing as bad publicity" is the Netflix ruling motto, apparently.
Meanwhile they ignore actual black African civilizations and historical leaders of ancient Sudan, Ethiopia, Eritrea, Djibouti, Somalia, Ghana, etc. Netflix story writers are a bunch of uncultured, uneducated, fat, virgin slobs who have never heard of great indigenous Sub-Saharan African rulers such as Piye of Kush (and Egypt's 25th dynasty), Amanirenas of Kush, Ezana of Axum, Kaleb of Axum, Musa I of Mali, Askia Muhammad I, Tewodros II, and Haile Selassie, or those who ventured far outside of Africa such as the Ethiopian monk, lexicographer, and translator Abba Gorgoryos who lived in 17th century Germany, or Malik Ambar who was once a slave in Ethiopia but rose to power as a prime minister and royal regent over the Ahmadnagar Sultanate of India in the 17th century (a grand military strategist against the Mughal Empire), or Yasuke who was once a slave from Portuguese East Africa (most likely Mozambique) but became a valued armed retainer of the Japanese daimyo Oda Nobunaga in the 16th century.