head to head
The Settlers 7: Paths to a Kingdom asks more than Portal 2, and the gap is reads.

Optimization · Pure Optimization
A first-person puzzle game where seeing the solution is the whole skill.

Optimization · Pure Optimization
Tuning interlocking production chains and racing victory-point routes.
Portal 2 leans Optimization (Pure Optimization); The Settlers 7: Paths to a Kingdom leans Optimization (Pure Optimization).
Portal 2 leans a little harder on execution, though the gap is small.
Portal 2
Portal placement requires some precision but timing is lenient.
The Settlers 7: Paths to a Kingdom
Slow-paced clicking - no twitch demand
The Settlers 7: Paths to a Kingdom leans clearly harder on reads.
Portal 2
No opponent; puzzles are static.
The Settlers 7: Paths to a Kingdom
Multiplayer victory-point races involve anticipating rival paths
The Settlers 7: Paths to a Kingdom leans clearly harder on variance.
Portal 2
Puzzles are deterministic with no randomness.
The Settlers 7: Paths to a Kingdom
Map resources are fixed and visible after scouting
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Portal 2
Solving the puzzle's logic IS the entire game.
The Settlers 7: Paths to a Kingdom
Production chains and victory-point routing are the whole game
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.