Board Thread:Episode Discussions/@comment-25319479-20180614110007/@comment-1512913-20180614185727

It's just a matter of technicalities. Kaguya had Hagoromo and Hamura with a human male, therefore, through Hagoromo and Hamura, chakra was spread into human population. In other words, Kaguya indeed unintentionally created the Shinobi. Kaguya provided chakra, Hagoromo provided chakra and Ninshu, Indra provided Ninjutsu.