1) how it relates to my own Greek identity,
2) how it relates to Black identity and
3) how it relates to the art form of theatre & film.
I think it is a positive from a Hellenic point of view as it opens up Greek civilization to Black audiences allowing for a more intimate relationship, this also runs the risk of cultural appropriation. I believe the pro outweighs the con here.
From a Black people's perspective, I think that industrial-level tokenism is the way most serious Black people would see these attempts of putting them in the shoes of famous white people. At the same time it creates an atmosphere of inclusion and it permits Black actors to play any type of role thus enabling them to participate in more genres(.ie periodicals) and not just roles representing themselves. White actors have been playing parts of any kind of ethnic identity without even bothering to ask and that brings us to...
Theatre was originally played only by men who would represent women, gods, animals and creatures. Hence the invention of the mask.
The identity of the actor has always been a non-issue as the point of theatre is to focus on the point rather than the skin, gender or type of the actor playing the role.
...take your common sense with you, and leave your prejudices behind...