The black actress is a form of 'oppression coding' to make the audience more sympathetic to the new perspective of the wicked witch as the 'victim', but in reality they ended up 'coding' her as a loud and obnoxious SJW stereotype of the racist 'bossy black lady' variety, that we all now associate with 'current thing black females'.
WE WUZ WITCHES N SHIT
The black actress is a form of 'oppression coding' to make the audience more sympathetic to the new perspective of the wicked witch as the 'victim', but in reality they ended up 'coding' her as a loud and obnoxious SJW stereotype of the racist 'bossy black lady' variety, that we all now associate with 'current thing black females'.