Issue #600 introduced Wonder Woman to an alternate timeline created by the Gods in which Themyscira had been destroyed and the Amazons scattered around the world. In this timeline, Diana is an orphan raised in New York who is learning to cope with her powers. The entire world has forgotten Wonder Woman's existence and the main story of this run was of Diana trying to restore reality even though she does not properly remember it herself. Diana has no memories of her prior adventures as Wonder Woman, recollecting her memories in bits and pieces and receiving different abilities and resources (such as the power of flight and her lasso) during the progression of her adventure. A trio of Death Goddesses called The Morrigan acted as Wonder Woman's main enemies. Diana ultimately defeats the evil goddesses and returns everything back to normal.
As a child, Steve Jr. had heard his late father's stories of adventures with Wonder Woman during World War II. It is essentially confirmed in the second season première that his father never introduced him to Wonder Woman and that he had never even seen her photographed. It is similarly implied that he and YN1 Diana Prince were unaware of each other. Diana is taken aback by the younger Steve's existence, implying that his father had never spoken of the boy to either Wonder Woman or YN1 Prince. This was particularly striking when she spoke to Steve Jr. about knowing his father well, from the j-shaped burn scar on his right shoulder, to the 20mm shell casing that he used as a paperweight.
Thus although by the modern depiction her accomplishments at the time seem ordinary, in that era they were more so. Diana Prince was originally an army nurse, but quickly attained the rank of lieutenant in Army Intelligence. This was partially a creative convenience so that she could be close to both Steve Trevor and received information which she needed to pursue her superheroics. In the real world though, this role in Army intelligence, even as the secretary to General Darnell, was still a rare position for a woman to hold in society. At this time as well, the character had her only real sidekicks in her history in the form of Etta Candy and the Holliday Girls. These characters gave the Wonder Woman a degree more of levity while also allowing the writers to focus on some issues which were more related to women. When Marston left the character, the strong driving force of the character to act as a strong moral guide and role model for female readers left as well and the character became more sensitive to the forces driving the industry as whole. Thus Wonder Woman changed somewhat to a more stereotypical woman. Her main interest was not always fighting crime, but for a time it became all in the interest of keeping Steve Trevor happy and interested in her for marriage. Also the backup stories featuring the Wonder Women of History were slowly phased out and replaced with features on marriage customs from around the world and trivial facts on random household objects.