head to head
Neither is simply harder - they are hard in different places. Grand Theft Auto V demands more reads; The Walking Dead: Saints & Sinners demands more variance.

Execution · Practiced Mastery
Sandbox crime playground spanning shooting, driving, and a persistent online economy.

Execution · Practiced Mastery
Physical VR combat plus scavenging economy management under time pressure.
Grand Theft Auto V leans Execution (Practiced Mastery); The Walking Dead: Saints & Sinners leans Execution (Practiced Mastery).
The Walking Dead: Saints & Sinners leans a little harder on execution, though the gap is small.
Grand Theft Auto V
Driving and shooting demand decent inputs.
The Walking Dead: Saints & Sinners
Physical VR stabs, aim and reloads under pressure are real skill
Grand Theft Auto V leans clearly harder on reads.
Grand Theft Auto V
Online PvP exists but mostly gear/positioning, not modeling.
The Walking Dead: Saints & Sinners
Walkers and human NPCs follow scripted behaviour
The Walking Dead: Saints & Sinners leans clearly harder on variance.
Grand Theft Auto V
Some mission and lobby randomness.
The Walking Dead: Saints & Sinners
Scavenging finds and encounter layouts vary per run
The Walking Dead: Saints & Sinners leans clearly harder on optimization.
Grand Theft Auto V
Heists, money loops, builds learnable.
The Walking Dead: Saints & Sinners
Crafting economy, stamina and route planning drive survival
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.