[Q]

I am pretty sure that this is not functional.
The armor points may vary because there is a random choice of armor type used, but the hull tonnage taken by armor or shields remain constant in the different difficulty levels.
The most obvious observation that the tonnage of enemy ships is not changed by the selected difficulty level is however that at easy level the total tonnage occupied in the Abbidon starbase is aroud 2100kt. There should be a maximum limit of 2000kT (80% of 2500).