I like to complain about putting blacks in historical roles that were white people, but I really like Denzel. And anyway, MacBeth is almost mythical so I don’t think it matters too much. I like everything the Coens do and I like Denzel and Francis a lot.
Imho the bard transcends race. There are many exceptional Shakespearien actors in the UK who happen to be of African descent. Watch Ralph Feinnes version of Coriolanus! It is epic!!