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
Linear postwar crime story driven by cover shootouts and atmosphere.

Execution · Practiced Mastery
A cinematic open-world western leaning on shooting feel and atmosphere.
Mafia II leans Execution (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.
Mafia II
Cover shooting and fistfight timing
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.
Mafia II
Enemies are scripted
Red Dead Redemption 2
Enemies use scripted AI patterns, not adaptation.
Red Dead Redemption 2 leans a little harder on variance, though the gap is small.
Mafia II
Story missions are fixed
Red Dead Redemption 2
Some hunting and weather randomness, lightly hidden.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Mafia II
Modest; learning encounter layouts
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.