Weight training equipment lasts decades all the time. It's just big piles of metal, it's not hard to get right.

What actually prompted the engineering-CYA "should" is if the Android tablet is controlling some sort of robotic system for selecting weight sizes, that that system might have an expected life span on par with a tablet, being a physical thing moving around some pins or something in a potentially hostile user environment. That'll break long before anything else would.