There's no doubt about that, I wouldn't expect some medieval huscarl donned 24 kg of maile and paid at least 50 shillings (about 5 mark) of silver for the sheer heck of it.
However leather on its own reputedly could withstand slashes as well as maile. What it couldn't take as well were razor sharp edges and thrusts. But then again leather provides some protection at a fraction of the weight and cost of maile.
In my own opinion later legionaries appeared much like that in the Byzantine frescoes. A leather cuirass with the addition of short maile or scale shirt protecting the torso.