*I once dated a guy who had a [pretend] Samurai sword on his wall.
I started talking about the way they used to be made, with the thousands of folds to keep it sharp for a lifetime and the history of them [I studied Japanese as well for a year, and was obsessed with the history in my early 20s].
Completely blank. No idea or interest about anything to do with swords. Just a sword on the wall. Potential red flag right there.*
sharp for a lifetime? it was pig iron it had to be folded thousands of times to make it usable and clay tempered to draw out the martensite on one side of the blade only otherwise they would be useless, it certainly wasn't sharp for a lifetime they had to be cleaned and oiled endlessly as they rusted as soon as you looked at them.
despite all the japanese romaticising them they were inferior steel to western steel, most of their lore comes from fighting the mongols whos swords were absolute junk too, even worse.
The vikings had amazing steel as did india.