OK lets make it easier. Your average consumer is a moron. They feel about things they do not think about things. So lets simplify.
Women's evolutionary power base is sex. It is great and amazing and got us from small group scavengers to the moon. 
Men's evolutionary power base is violence. It kept wolves, bears, and other men out of our caves while the women figured things out.

Now as anime primarily markets to young males you have to look at the evolutionary power base and ask "Why do women not out number men 20+:1 if men's power base leads them to kill each other?"

Well for that we have to look at adaptations. Violent men were valuable even when women judged them unacceptable for passing on genes. The way our species dealt with this is "hero worship" (and the unfortunate r4pe during wars/battles/raids).
Males can avoid violence by living vicariously through the victories of their heroes. You can look at citations for the affects of sports team win/loss on male T levels or you can simply look at male human animal years with "my dad can beat up your dad"; it is wired in.

So to cater to this makes legend/prophesy creation easy. Just cater to the wiring.

Oh Jesus, I though we cleaned up the censoring years ago. we are writers not children.