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 choice-driven narrative adventure testing little beyond attention to consequences.

Optimization · Light / Casual
A first-person mystery about a fire lookout in a Wyoming forest.
Dreamfall Chapters leans Optimization (Light / Casual); Firewatch 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.
Dreamfall Chapters
Walking and dialogue selection demand nothing physical
Firewatch
Walking and radio dialogue only.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Dreamfall Chapters
No adaptive opposition in a scripted narrative
Firewatch
No adaptive opposition.
Dreamfall Chapters leans a little harder on variance, though the gap is small.
Dreamfall Chapters
Choice consequences are hidden until they land
Firewatch
Minor environmental discoveries.
Dreamfall Chapters leans a little harder on optimization, though the gap is small.
Dreamfall Chapters
Light puzzles and choice mapping, mostly story consumption
Firewatch
Few systems to optimize.
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.