Linothorax vs Quilted linen vs spolas

[Lysimachos]

On top of that, if the illustration is supposed to be representing segmented plate they would not be aligned vertically, it removes any flexibility at the waist. They would be horizontally aligned.

Perhaps not, the T-Y largely follows the form of the old style bronze cuirasse which obviously was inflexible. The T-Y is high enough on the waist to allow bending in the middle without flexible panels. Even if these panels were stiffened textile, they would retard bending if too long.

In a much later context, many of the coats-of-plates from Visby had a similar vertical alignment. For example, armours 8-15 all have long vertically-aligned plates for the lower torso. Perhaps not good for bending at the waist, but better for wrapping the armor around the body and requiring less precise shaping of the plates?