Keep in mind I only read the first third of it, but the secret society of almost entirely white people who trace their lineage back to one of the arthurian personalities certainly think they own it. Our narrator, who notes that her ancestry records are untraceable because her ancestors were enslaved, is pretty alienated by the whole thing, but also a little drawn in by the legend and the set dressing. And there are hints of a separate magic system at play that the arthurian types don't understand. So I don't know how it would all have fallen out.