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
Pioneering six-degrees-of-freedom shooter through robot-infested mines.

Execution · Pure Mechanics
Punishing rally car control at the limit, supported by setup and stage knowledge.
Descent leans Execution (Practiced Mastery); Dirt Rally leans Execution (Pure Mechanics).
Dirt Rally leans a little harder on execution, though the gap is small.
Descent
Full 6DOF control and aim under disorientation is the test
Dirt Rally
Unforgiving car control on loose surfaces is the entire test
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Descent
Scripted robot behaviors, no adaptation
Dirt Rally
Solo time trials against the clock, no adaptive rival
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Descent
Mine layouts fixed; ambushes surprise only once
Dirt Rally
Weather and surface degradation vary between stages
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Descent
Route memorization and weapon economy reward optimization
Dirt Rally
Pacenote interpretation, setup tuning and stage memorisation
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.