The place of Wonder Woman in this DC movie world is a big question mark. So she was involved in World War I--but I guess that's so removed from time and her part is so unreported that she's been almost forgotten. Yet what did she do all that time?
Had Diana inspired people and become a world legend, then when Superman arrived on the scene, he would have been the Wonder Man to her Wonder Woman. The fact that he wasn't suggests that Diana let the grass grow.
For MAN OF STEEL and BATMAN V SUPERMAN to make sense, then there can't be a history of Wonder Woman fighting for human rights. However, Diana is not the kind of person who would just sit still for a hundred years.