I get that for a rare material and in a world where swords are a main weapon, you'd want to make a sword from the super material. That said: if it reacts to spirit energy and is found in small amounts isnt that perfect to make bullets? Or like bomb collars to prevent anyone from using sorcery...
One of my biggest gripes with jjk is that japan specifically can only harbor cursed energy except a handful of people elsewhere. Afaik it was cause of tengen's barriers but now its a little different. Regardless, it really narrows down the potential for more side stories that don't involve...
So mahoraga was only untamable because any user who forfeits participation (suspended animation) just dies unless someone not in the ritual defeats him? I'm a little confused how Yuka still dies even if he is defeated (unless I just misinterpreted, I am a jjk fan after all). Pretty much begging...