That's such a derp picture on page 4.
Yeah, if you're just leveling, you probably don't want to use the expensive stuff. But if you want to create something to actually use...
All steel seems like it'd be pretty heavy.
Curve isn't exactly what a katana would have, but she's cheating when making them, so result may vary.
A katana is usually short compared to European two-handed swords, more similar to one-handed swords but heavier, so it shouldn't be that hard to draw. Normally I'd say the slight curve helps a bit as well, but her version has an almost entirely straight blade and curved handle.
That slice doesn't seem to follow the draw she made.
"A nation with Japan-esque culture, something that commonly occurs in fantasy settings."
Very much so. And as much as some people like to complain about Japanese stuff, it's not just in Japanese fantasy.
aaah yes... glorious Nihon steel.... that is somehow more difficult to produce...
Well, starting out with worse materials and finding out various complex ways of making it acceptable is harder than just starting with good steel (though her cheat skills should make up for that). But it's not like it's unique anyway. Maybe the specific methods, but people all over the world figured out their own ways to deal with the qualities they had access to.
It would also make sense that the price is high because those swords are glorified, and not because they're actually better. Since that's a good reflection of how it is in the real world.