head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is reads, and it is a single point.

Optimization · Light / Casual
A first-person mystery about a fire lookout in a Wyoming forest.

Optimization · Light / Casual
A point-and-click detective adventure focused on investigation and puzzle-solving.
Firewatch leans Optimization (Light / Casual); Still Life 2 leans Optimization (Light / Casual).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Firewatch
Walking and radio dialogue only.
Still Life 2
no physical skill beyond puzzle interaction
Still Life 2 leans a little harder on reads, though the gap is small.
Firewatch
No adaptive opposition.
Still Life 2
no adversarial opponent, investigative narrative
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Firewatch
Minor environmental discoveries.
Still Life 2
minimal randomness, fixed puzzle solutions
Still Life 2 leans a little harder on optimization, though the gap is small.
Firewatch
Few systems to optimize.
Still Life 2
puzzle logic solving is the main systems layer
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.