Well DC did kill her off quietly in the 90s while Hippolyta took the mantle but then just as quietly and quickly brought Diana back to make an impact.
However, they are other characters like Captain Marvel and Flash who have successfully passed the mantle that their successors have become more popular than them.
Should DC instead of hard and soft rebooting her every couple of years just kill her off in an epic manner or give her Godhood and pass the mantle to a new character?