[@RoflsMazoy] That makes sense. I was more thinking along the lines of human knowledge of arts, or at least the basics that are taught to everyone, practitioners or otherwise, being more likely to be derived from a scientific breakdown of arts and whatever got officially recognised by humans during the war and thereafter, rather than whatever methods the Yokai used to cultivate their knowledge and from that perspective 50 years being a relatively short period of time for those more niche specialised fields to develop. Especially considering that without a decent understanding of how arts work it makes little sense to group them into fields that may not actually be correlated. 

On the other hand, this way makes more sense if human knowledge of arts has since its discovery been more been derived from being taught by or directly copied from Yokai, which looking back now seems to be how it's done. So ignore me I'm an idiot.

Just to throw an idea out there, I still think it makes more sense for members of the agency and probably to a lesser degree the general public to have been taught a little about arts and yokai from the perspective of human scientific breakdown as well as some specific examples of arts. Simplified stuff in similar to the sort of things one might learn in basic highschool science. Hence one of the first things new recruits into the Agency or practitioners of any form of art would need to learn would be to abandon their oversimplified preconseptions.