head to head
Skate 2 asks more than Half-Life 2, and the gap is execution.

Execution · Pure Mechanics
Landmark FPS built on physics puzzles and tight gunplay.

Execution · Pure Mechanics
A skateboarding sandbox where tricks come from analog stick flicks rather than button combos.
Half-Life 2 leans Execution (Pure Mechanics); Skate 2 leans Execution (Pure Mechanics).
Skate 2 leans clearly harder on execution.
Half-Life 2
Gravity gun and shooting demand precision.
Skate 2
Flick-it stick controls map tricks to genuine manual dexterity
Half-Life 2 leans a little harder on reads, though the gap is small.
Half-Life 2
Combine AI scripted, non-adaptive.
Skate 2
Solo sandbox, no adaptive opposition
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Half-Life 2
Almost no randomness.
Skate 2
Static city, deterministic physics
Skate 2 leans a little harder on optimization, though the gap is small.
Half-Life 2
Linear progression with no builds.
Skate 2
Spot selection and line planning improve scores
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.