re: Why did these names of male children become so popular?

The root cause is the slow death of family names. My son’s first name is my wife’s maiden name and my daughter is named after a great aunt on one side and great grandmother on the other side. Our first instinct when naming kids was to look within the family. Nobody seems to do that anymore. I place a lot of stock in kids with normal names. My daughter (6) has a kid in her class named Greg. I like him based purely off his name because 6 yo Greg’s just don’t exist anymore.