I feel like headcanoning Sasha as black and making NotSasha white takes away a large part of horror of the whole situation, especially with how it’s treated by the fandom: made into a joke and laughed off.
I’ve always seen it like this: The terrifying part is not that someone you knew got replaced by an entirely different person. It’s that the new person is Not Them. They are wrong in a thousand little ways. Their face is round where before it was angular. Their front teeth are now straight where they used to be crooked. They no longer have the little mole near their chin. All the little quirks that made a person themselves, that made them unique and special to you - gone.
I understand that it would be different depending on the kind of relationship you had with the person who got replaced. But making it into “the person you knew is gone and there’s this rando there instead” is misunderstanding how this is meant to be scary. Especially since fans do it just to laugh it off as the NotThem being racist. Everyone’s forgetting how terrifying suddenly not recognizing someone you knew would be. It is that deep actually
I also think that it’s icky, but I can’t quite put my finger on it and am in no position to judge that