head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Execution · Pure Mechanics
Arcade reflexes against memorisable alien swarm patterns built to eat quarters.

Execution · Pure Mechanics
An open-world extreme sports game about carving ski, snowboard, and wingsuit lines down the Alps.
Aliens leans Execution (Pure Mechanics); Steep leans Execution (Pure Mechanics).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Aliens
Arcade dodging and shooting under swarm pressure is the test
Steep
Landing tricks and threading lines at speed is hands-first
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Aliens
Xenomorph waves follow scripted arcade patterns
Steep
The mountain never adapts to you
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Aliens
Stage layouts and spawns are fixed
Steep
Fixed terrain, deterministic physics
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Aliens
Learning spawn points and weapon pickups carries credit-saving runs
Steep
Line choice and trick scoring math reward study
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.