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 · Practiced Mastery
An encyclopedic driving simulator spanning 700 cars and decades of automotive history.

Execution · Practiced Mastery
Movement execution and route optimisation through a fixed, mappable planet.
Gran Turismo 4 leans Execution (Practiced Mastery); Super Metroid leans Execution (Practiced Mastery).
Gran Turismo 4 leans a little harder on execution, though the gap is small.
Gran Turismo 4
Hundreds of cars all demand precise inputs
Super Metroid
Wall-jumps, shinesparks and boss dodges demand precise inputs
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Gran Turismo 4
Fixed-line AI offers no adaptive opposition
Super Metroid
Bosses cycle fixed patterns, never adapting
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Gran Turismo 4
Deterministic outside slight tyre wear modelling
Super Metroid
Item and route knowledge is fixed once discovered
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Gran Turismo 4
Event-by-event car and tune selection is deeply solvable
Super Metroid
Sequence-breaking route optimisation is the enduring meta-game
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.