head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is reads, and it is a single point.

Execution · Practiced Mastery
A scripted cinematic driving game testing modest car control through fixed set-pieces.

Execution · Practiced Mastery
A grittier crime story where weighty driving and gunplay carry the experience.
Fast & Furious: Crossroads leans Execution (Practiced Mastery); Grand Theft Auto IV leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Fast & Furious: Crossroads
Driving and stunt timing are the only real demands
Grand Theft Auto IV
Heavier driving and cover shooting reward control.
Grand Theft Auto IV leans a little harder on reads, though the gap is small.
Fast & Furious: Crossroads
Scripted chase sequences never adapt
Grand Theft Auto IV
Scripted AI, no adaptive opponent modeling.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Fast & Furious: Crossroads
Set-piece events play out identically each run
Grand Theft Auto IV
Minor mission variance.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Fast & Furious: Crossroads
Light racing lines, nothing deep to solve
Grand Theft Auto IV
Mission routing and weapon picks learnable.
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.