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 car control across loose surfaces, weather and door-to-door packs.

Execution · Pure Mechanics
Drift execution and learned racing lines through destructible city tracks.
Dirt 5 leans Execution (Pure Mechanics); Ridge Racer Unbounded 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.
Dirt 5
Sliding off-road cars on mixed surfaces is the whole test
Ridge Racer Unbounded
Drift control and boost timing decide every race
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Dirt 5
Pack racing adds light wheel-to-wheel jockeying
Ridge Racer Unbounded
Online rivals allow mild positional prediction
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Dirt 5
Dynamic weather shifts grip unpredictably
Ridge Racer Unbounded
Destruction chaos adds modest track noise
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Dirt 5
Car class knowledge and line choice reward study
Ridge Racer Unbounded
Learning racing lines and shortcut routes rewards 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.