In Leisure Suit Larry this was deliberate. There was a puzzle where you needed to get Larry strong enough to open a grate or something. You could do that by doing a certain number of repetitions on a weight lifting thingy in a gym. The number of repetitions depended on the speed of your CPU. Of course the time for the animation per repetition stayed the same.
Al Lowe wanted to punish those posh people with their fancy 3’86 machines. Funny joke back then. Nowadays it’s practically impossible. I wonder what they did with this puzzle in ScummVM.