head to head
American Truck Simulator asks more than Portal, and the gap is variance.

Optimization · Pure Optimization
American trucking sim about long hauls and growth.

Optimization · Pure Optimization
The portal-gun puzzle game whose solutions are everything.
American Truck Simulator leans Optimization (Pure Optimization); Portal leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
American Truck Simulator
Truck handling and trailer parking
Portal
Portal placement timing modest.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
American Truck Simulator
No adaptive opponents
Portal
No adversary modeling player.
American Truck Simulator leans clearly harder on variance.
American Truck Simulator
Traffic and weather variance
Portal
Deterministic chambers; no randomness.
Portal leans a little harder on optimization, though the gap is small.
American Truck Simulator
Fleet, garages, route economics
Portal
Pure puzzle-solving optimization.
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.