I don't think this conflict is about how some people turned black.
The fact that people peoples live in tents tells me that this is a vision of conflict about the temple, one kind of temple people against another kind of temple people. The fact that the winners are named "Canaan," the pre-Israelite, pagan name of the land of Israel, and are cursed for, suggests to me that we're reading here loser's history, like the Dead Sea Scrolls, 1 Enoch, and -- I think -- Isaiah.
Enoch's people are the tent people of Shum. Though they lose and are driven out, the winners are cursed. Enoch will continue to preach, except to wicked Canaan.