Originally Posted by
MajorHoy
Well, so far it hasn't been revealed that Hippolyta previously ever left Themyscira and had adventures in the United States, which would sort of lessen Diana's decision to do so at a later date in time.
And if Hippolyta was "Wonder Woman" during WWII, that means Diana is not the first one have that mantle.
Basically, it would knock Diana down to a legacy character following in her mother's footsteps, sort of like a second-generation hero, which isn't really what Diana has been before.