what jshirley said. also, what is commonly known as the 'katana' also evolved with armor, by getting shorter and shorter. the curvature and type of point evolved and varied widely based on how it would be used, and whether it was expected to be used against armor or light clothing.
if you mean they're not magical, then ok. but generally, your statement is not accurate. the steel isn't as good as what can be had today, but it's fantastic for its time and there were plenty of high quality. i've owned several that ranged from 200 to 700 years old, some with papers. two in particular were roughly 500 and 700 years old. both were quite serviceable, despite the former being polished many times to the point that it was quite thin. i still used it daily for many years when i studied iaido, including cutting with it often.
only in the sense that ccw are also rarely used in actual combat. meaning, it's quite rare for anyone to be involved in combat.The Katana is probably the most overrated sword in the history of the world. They were more of a ceremonial weapon and were rarely used in actual combat.
They're not nearly as strong as some make them out to be either because the steel used to make them was of such poor quality. They're just too delicate and easily damaged to be of any use in actual combat.
if you mean they're not magical, then ok. but generally, your statement is not accurate. the steel isn't as good as what can be had today, but it's fantastic for its time and there were plenty of high quality. i've owned several that ranged from 200 to 700 years old, some with papers. two in particular were roughly 500 and 700 years old. both were quite serviceable, despite the former being polished many times to the point that it was quite thin. i still used it daily for many years when i studied iaido, including cutting with it often.