The swords also sucked. Their effectiveness came from the training of the soldiers and allowed them to make what are, essentially, the original Pakistani steel. Because they did have a military industrial complex they were big into recycling broken weapons, further reducing the need for high quality products. The standard issue Chinese Jian style sword was the same kind of thing. All about volume production.There were weapons for the wealthy and powerful of much high quality than the Legionaries (and Chinese) infantry used, but they were not the standard.

Popular history gets things kind of muddled because the price of steel weapons skyrocketed as the Western Roman Empire crumbled. During the Middle Ages steel weapons were quite uncommon and served as a mark of wealth that often passed through multiple generations of a family, sometimes reaching near legendary status. That concept was retroactively, and incorrectly, applied to Roman weapons.