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

Execution · Pure Mechanics
A physics comedy about an octopus in a suit flailing through fatherhood without blowing his cover.

Execution · Pure Mechanics
A fast arcade rail-shooter testing reflexes through surreal scrolling stages.
Octodad: Dadliest Catch leans Execution (Pure Mechanics); Space Harrier II leans Execution (Pure Mechanics).
Space Harrier II leans a little harder on execution, though the gap is small.
Octodad: Dadliest Catch
Deliberately clumsy limb controls are the whole challenge
Space Harrier II
reflex dodging in fast rail-shooter
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Octodad: Dadliest Catch
No opponents, just suspicion meters
Space Harrier II
fixed enemy patterns, no adaptation
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Octodad: Dadliest Catch
Physics wobble adds slapstick unpredictability
Space Harrier II
minimal randomness
Octodad: Dadliest Catch leans a little harder on optimization, though the gap is small.
Octodad: Dadliest Catch
Simple objectives, little system depth
Space Harrier II
little beyond memorizing enemy waves
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.