You give a talk. People show up. They clap at the end. Does it really matter what some title on some conference website is? The communication was perhaps a bit more confusing and hectic than it should have been, but does that really matter? Is that really a big deal?
I don't even understand why anyone would overly care about this in the first place, and now it's also an example of systemic bias against black people, "cruel", and "heartless"?
If the talk had been outright cancelled: sure, what would have been a right dick move. But from what I can see all that happened is that the "status" (that I don't think many pay attention to) got "downgraded" and (maybe) moved to a different timeslot. I'm just confused why this would spark such strong reactions.