I am not gonna argue your main point here as you are correct. Only that the Japanese had swords made with the specific purpose/intent of a battlefield weapon.
Japanese swords were never meant for war. All shapes and forms of them were in the end were developed for individual self-defence. Doesnt mean swords werent used in some battles, but thats all negligible. Here some fun stastistics:
"According to data from the Warring States period in Japan, the majority of damage on the battlefield was caused by arrows, accounting for 38.6% of all injuries. Following this was damage caused by firearms, at 22.2%. Close combat weapons like the long spear or yari accounted for 20.8%. Intriguingly, after the yari, the next weapon causing the most injuries wasn't the Japanese sword, but rather stones, accounting for 11.3% of total injuries. Damage caused by the Japanese sword, or uchigatana, was a mere 4.5%. It's worth noting that these statistics predominantly concern foot soldiers, whose armor was considerably superior to the average infantry."
In all cultures arocss the world throught history that made swords with the first intent of its application being used in warfare on a battlefield, said swords were always shaped for stabbing not slashing and intended to be used in tamdem with a shield (excluding some swords for cavalry). Japanese swords were neither made for stabbing or with a shield use in mind.
Fun fact, the most use the "katana" ever saw in a war was between 1941-1945.