I mean, this already happened. Ted Danson was semi-cancelled in the early 90s for wearing blackface to a Friar's Club roast of his then-girlfriend Whoopi Goldberg.
Blackface being problematic isn't something we just figured out in the last 12 years, and people trying to do something funny with it anyway isn't new either.
I don't disagree with the fact that blackface is an old phenomenon, I think RDJ's prodigal-son-returns factor and headlining a tentpole summer blockbuster helped brace the impact a bit.