Katanas are not actually that sharp. I mean, it’ll kill you just fine, but it’s almost more like a big machete than a sword.
Yeah there is so much disinformation about katanas from basement kids in the 90s/00s.
They are really impressive cause shit steel ended making a pretty good sword but most of the trick is the curve and the sawing action it makes you do if you swing correctly to cut through stuff like a chefs knife. But you do want it sharp, and free of burs so that it doesn’t get stuck part way in.
But you’d be up against a big stick with metal bolts in it that would win the fight mostly anyways.
Nah, they are sharp, but flimsy.
They were designed to cut-off unprotected limbs. Since iron was very scarce in feudal Japan. So metal armours weren’t really a thing for the majority.
Put them up against an European sword, where they did have more pure iron ore and they will break.