The idea here is interesting, but I wonder if anyone has tried to actually put it to the test. Not out of any personal desire to replace reasoned argument with statistics, mind, but simply because it's pretty clear now that anything short of repeatedly replicated psychometric data will be dismissed without consideration if it disagrees with the doctrine of HNU.
Apparently there are such things as a Guilt Inventory, so assuming it's actually as reliable as it's supposed to be it seems to reason that one could take Guilt Inventories of various populations and see what shakes out.
Without saying this is true, I'm not sure how much this would disagree with Human Neurological Uniformity. It seems to me that guilt would be present everywhere but if the culture is one where shaming is used a lot, it wouldn't get as much exercise, which could lead to this.
Related: The Psychological Diversity of Mankind, An African Folktale, many of the more interesting infanticide & abortion debates on this site
A fascinating post that however might need some background reading, most relevant material is linked in the article itself. I encourage reading up on the material.
Link to article.
Stories about changelings replacing babies and the recommended course of action being basically to expose the child is not a human universal, they are found only in European cultures. These rely more heavily on guilt and less on shame to regulate behavior than most other human societies. This may not be a coincidence. The stories look like they work as a ready made rationalization to reduce guilt from infanticide. Common problems often acquire common solutions like this.