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.

Optimization · Practiced Mastery
The genre-defining 3D open-world crime game set in Liberty City.

Execution · Practiced Mastery
A cinematic open-world western leaning on shooting feel and atmosphere.
Grand Theft Auto III leans Optimization (Practiced Mastery); Red Dead Redemption 2 leans Execution (Practiced Mastery).
Red Dead Redemption 2 leans a little harder on execution, though the gap is small.
Grand Theft Auto III
Driving and clunky gunplay set a modest physical bar
Red Dead Redemption 2
Gunplay and Dead Eye reward aim and timing.
Red Dead Redemption 2 leans a little harder on reads, though the gap is small.
Grand Theft Auto III
Enemies are scripted; nothing models the player
Red Dead Redemption 2
Enemies use scripted AI patterns, not adaptation.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Grand Theft Auto III
Pedestrian and traffic chaos lightly randomises encounters
Red Dead Redemption 2
Some hunting and weather randomness, lightly hidden.
Grand Theft Auto III leans a little harder on optimization, though the gap is small.
Grand Theft Auto III
Mission routing and city knowledge are learnable systems
Red Dead Redemption 2
Loadouts and routes solvable but loose.
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.