Explanation: Roman men in general, and Roman soldiers in particular, disdained trousers until around the mid-2nd century AD (they started wearing trousers a bit earlier in the colder regions of the Empire, but it wouldn't catch on for a while). They considered it very unmanly and unRoman! So they wore tunics which, of course, could not be too long, or else they would restrict movement. As such, a legion of Roman soldiers would be showing a LOT of leg 🥵
Amusingly enough, this was acknowledged as potentially sexy by the Romans themselves - Mark Antony, one of Caesar's top generals and a notorious ladies' man, was condemned by his enemies for wearing SCANDALOUSLY short tunics to show off his sexy legs. What a tease he was!