so much racism disguised as 'confusion' in this thread....
we were confused
they were confused
it will cause confusion
But there is a small element that I really think that it is relative to where you live. I live in London so my life is multicultural, my kids lives are multicultural, my niece and nephew are not the same colour as their parents (adoption). Kids round here grow up aware of colour, but do not judge or question based on it. The schools are mixed, families are blended and not all one colour - no one bats an eyelid. So seeing this in theatre and on telly is not an issue
I had no issues with 'understanding' Wicked Little Letters, Ballamory, David Coperfield, Bridgerton and really it isn't that confusing.
Re-writing characters as black when they weren't is not an issue as long as race isn't a part of the character's story.
Conversely, MLK, Rosa Parks, and most black historical figures have faced issues because of their race and it makes up part of their story. Even Mary Secole was overlooked in favour of Florence Nightingale so her race played a part in who she ws.
On the whole, a white person who has never faced race issues can be played by anyone, black or white - the fuss when Hermione was cast as black in Cursed Child was ridiculous.
There are so many wonderful black actors out there who were not getting roles because people assumed the character would be white. Young actors ended up playing gang members and drug dealers - there is no reason why these good young black actors shouldn't play more roles and a conscious decision made to be more colourblind in casting.
Soon we wont notice and soon there will be more and more black roles - and in the meantime if in a fictional or 'based on a true story' film plays around with race what does it really matter?