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

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

Variance · Light / Casual
Deliberately broken physics sandbox about a goat causing mayhem.
Firewatch leans Optimization (Light / Casual); Goat Simulator leans Variance (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.
Goat Simulator
Janky physics resist precision on purpose
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Firewatch
No adaptive opposition.
Goat Simulator
No opposition; pure sandbox
Goat Simulator leans a little harder on variance, though the gap is small.
Firewatch
Minor environmental discoveries.
Goat Simulator
Ragdoll chaos is unpredictable but stakes-free
Firewatch leans a little harder on optimization, though the gap is small.
Firewatch
Few systems to optimize.
Goat Simulator
Score combos exist but barely matter
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.