I’d like to see a source for that shit about bayonets. As I recall they were hailed for enabling soldiers to carry a secondary weapon in the event their weapon jammed, misfired or straight missed (all very common during the period bayonets were common), or later in the event they ran out of ammo. It was the same as as archers carrying an arming sword but without the need to draw it.

Stabbing weapons and daggers were also, if anything, MORE common than swords in the medieval period. Especially on battlefields: doesn’t matter how badass you are you ain’t hacking through a plate harness with that flamberge. If anything you’re gonna half-sword that thing and ram it through the visor, or into the arm pit, or down the gorget. And a slender dagger works a hell of a lot better. But if you’re a knight you’re probably using a heavy axe, a pick or a big blunt fuck-you anyway.

Katanas as art is relatively modern: they were designed as tools for killing people in what we would consider very light armor, or none at all. The curvature wasn’t sufficient to aid in cutting and prior to differential tempering they were pretty shit as swords go. They weren’t even primary weapons in warfare: no sword ever was, except maybe the aforementioned flamberge and other big two-handed swords. Samurai used yumi bows or yari spears as primary weapons, swords were backups, honor symbols and tools for executing prisoners and finishing combatants.