Of course, most zombies ARE just fleshy bits, and the Katana will remain quite good at killing them. (At least the real Katana, we’re going to have “display” swords of all types as well hanging around, heheh)
When I finish my combat rewrite, zombies will actually have a pretty decent resistance to piercing, so the katana will probably be one of the better swords for dealing with them.
The problem with spears as that as awesome as they are, they have disadvantages - they get stuck in things, they snap, they get thrown (which is an advantage, but then leaves you sans spear) and they tend to be heavy and bulky. Swords, katanas included, tended to be the equivalent of the modern day pistol as compared to the militaries primary weapon, rifles - they were good for situations where you didn’t want to lug around a larger weapon, were handy for close combat situations in tight places, were useful as a backup weapon if you lost your primary weapon, etc. and so on. You’d generally only lug your spear and bow around when you were expecting combat, but the katana (like swords in general) could be carried everywhere much more easily. Since Samurai generally spent more time acting as police than they did as warriors, it was probably more common to see them carrying a sword than a spear and bow.
Katana’s were also pretty decent weapons to use from horseback. Notice the similarities between the katana and it’s European kin, the saber.
Essentially: It wasn’t a bad weapon, at all, but most weapons existed to serve a purpose, and the purpose of weapons in different regions tended to differ. The katana was a very effective tool for the purpose it served, but that purpose generally wasn’t “everything” like people seem to think it was.
A primary purpose of the Katana for Samurai was as a symbol - the pairing of a katana and smaller sword (known as daishō) was legally limited to samurai in many times and places, so wearing one was an effective way to let people know not to mess with you.
Samurai equipment generally included…
Yumi: (Later, this was replaced by the tanegashima (a Matchlock rifle), which became the go-to samurai weapon)
Yari: (Replaced Naginata in 15th century)
Wakazashi/Tanto: Technically, this is closer to a pistol. The equivalent of the knive’s European’s and everyone else wore all the time.
Katana/Tachi: Basic Sword/Version specialized for horseback
The thing to remember is that honor-wise, you got a lot more respect as a Samurai for killing more people. So decent sniping weapons (bow/rifle) were preferred for combat, and quick cutting weapons (katana) for dealing with routed enemies.
The Yari was the most effective weapon for difficult fights, and the primary weapon for actual warfare, but there wasn’t a whole lot of murder-credit you could earn for it - it was most useful against targets that could effectively fight back and had closed enough that you couldn’t shoot them.
Some Samurai also has some different favored weapon, and like European knights many weren’t actually professional warriors, and would often use what they were most familiar with instead of the best weapon for a given situation, esp. since their primary duties were dealing with peasant uprisings or criminals rather than fighting armies. Samurai was actually an entire class of people - Samurai women, for example, were expected to stay at home and raise the children (and also handle everything concerning money), and thus were usually only trained in naginata and knife-fighting instead of getting any sort of war-specific training, and didn’t even use a katana at all!