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
Capcom's infamously punishing arcade platformer that makes you beat it twice for the real ending.

Execution · Practiced Mastery
A precision metroidvania about learning fixed boss patterns and tight platforming.
Ghosts 'n Goblins leans Execution (Pure Mechanics); Hollow Knight leans Execution (Practiced Mastery).
Ghosts 'n Goblins leans a little harder on execution, though the gap is small.
Ghosts 'n Goblins
Committed jumps and pixel-precise throws, no mercy
Hollow Knight
Precise platforming and pogo timing dominate hard content.
Hollow Knight leans a little harder on reads, though the gap is small.
Ghosts 'n Goblins
Enemy spawns are scripted
Hollow Knight
Bosses run scripted attack pools; not adaptive.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Ghosts 'n Goblins
Red Arremer movement adds slight noise
Hollow Knight
Negligible; world layout is fixed.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Ghosts 'n Goblins
Weapon choice and route memorisation are mandatory
Hollow Knight
Charm builds and boss routes are fully learnable.
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.