Taking a step back from fiction for a bit, as I was trying to make a point about Bracken’s Cube that I don’t think I made explicit enough. The cube is a way to generalize a population, and like all generalities it cannot portray the entire truth. The cube seeks to explain a political ideology based on racial, geographic, and economic indicators. This is fine, and using it as a predictive tool is completely legit, but we must really look at what the tool is, and isn’t.
The cube isn’t about sides, the cube is about volume. If you put every individual inside the “cube” where they fell on the three axis you would not end up with a perfect cube. It would look kinda like a lopsided pyramid or tear drop shape, with a large “poor floor” and small wealthy top skewed towards whites (we don’t have an even distribution of races in any country). No one perfectly exists at the sides or corners of the cube, each axis is a continuum. There will always be someone more successful, or poorer, or even whiter or blacker.