We could simply deny the existence of an explanatory gap. But the common sense of the Social Self is our default understanding of the way things are. Any alternative explanation, like the one offered by Generative Realism, should be able to reconcile with common sense. The story of origins in Part II attempts to do that. Another reason to look at the origin of the mind is children.
Children are obviously conscious human beings.
Each of us was one. Yet it is apparent to even a casual observer that the mind of a child is not like the mind of an adult. It's not simply that children and infants don't know as much stuff as we adults do. Rather, their minds seem to operate in a different manner. Whichever it is, we would be interested in the causal factors behind those changes.