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
Zero-gravity physics game about wrestling floppy cosmonaut limbs through space-station chores.

Execution · Pure Mechanics
An open-world extreme sports game about carving ski, snowboard, and wingsuit lines down the Alps.
Heavenly Bodies 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.
Heavenly Bodies
Deliberately awkward limb-by-limb zero-g control
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.
Heavenly Bodies
No opposition
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.
Heavenly Bodies
Fixed scenario layouts
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.
Heavenly Bodies
Task order and clever anchor points
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.