In essence, Jenkins suggests that Diana may win the day, but ultimately have her eyes opened to the reality of man’s world. Instead of grabbing up her sword, shield, armor, and taking responsibility for the world’s problems, she realizes she must step back and let it follow its own course. The real key point here isn’t whether or not Diana “walked away from mankind” – she admits as much to Bruce – but the esteem in which she held mankind as she surrendered any duty to save it.
Looking at it from the perspective Jenkins suggests, setting Diana up as simply observing mankind while holding onto love and hope for its future makes her role in Batman V Superman and Justice League even richer. You could argue that Superman is a perfect embodiment of the hero, the icon, the ‘savior’ she chose not to be for the world. Over the course of Snyder’s films that means Diana has seen her decision validated, given the torment Superman is put through… until his death shows how much impact a single hero can have.
At the very least, the world’s embrace of Superman after his death could give her hope she’s apparently been missing by the time she re-emerges. The events of BvS and the new threats of Justice League hopefully show her that mankind isn’t capable of defending itself from every enemy. And Unlike World War I, this threat is even beyond the guilt or responsibility of everyday humans… we assume. Unless you want to blame Lex Luthor. Always blame Lex Luthor.