Frustration

Spears are a great weapon for infantry, and they are far superior to a sword in both organized units (pikes specifically. All them people writing about pike blocks got smt right) and duels—just because of the easy thrusting nature of a spear, it’s really easy to take down someone with a heavier weapon like a large sword. The one big problem is that I’d imagine that spears can’t very easily pierce chain or plate.

Large swords are really only practical if you’ve got the armor to back it up, and that’s really expensive.

Depending on if we’ve got iron yet, it tell ‘em to keep crossbows/regular old bows handy, cuz those can safely pierce heavier armor. They can pierce it very very well. Crossbow especially because it drastically reduced the training needed for one, far less equipped soldier to take down an armored knight at a distance. 

Small swords can make a nice medium between spears and large swords. Large swords prefer fluid motions that are optimized to conserve energy as much as possible. Smaller swords do not prefer fluid motion, and can be handled with a shield that prefers defensive motions. Their weight makes them slightly better at overcoming armor or shields, but not such that they are thaaat much better to use.

Also, yeah, material costs are extremely apparent. This was worse for bronze, which needed more buck for the same bang. The Iron Age was cool though, because until then, it was underutilized as a resource because people didn’t have the technology to even process the metal, much less make blades from it.