head to head
Kingdom Hearts III asks more than Grand Theft Auto V, and the gap is optimization.

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

Execution · Practiced Mastery
The saga's flashy conclusion sending Sora through Pixar and Disney worlds toward the Keyblade War.
Grand Theft Auto V leans Execution (Practiced Mastery); Kingdom Hearts III leans Execution (Practiced Mastery).
Kingdom Hearts III leans a little harder on execution, though the gap is small.
Grand Theft Auto V
Driving and shooting demand decent inputs.
Kingdom Hearts III
Limit Cut bosses require sharp reactions
Grand Theft Auto V leans a little harder on reads, though the gap is small.
Grand Theft Auto V
Online PvP exists but mostly gear/positioning, not modeling.
Kingdom Hearts III
All opposition is scripted spectacle
Grand Theft Auto V leans a little harder on variance, though the gap is small.
Grand Theft Auto V
Some mission and lobby randomness.
Kingdom Hearts III
Minimal hidden systems
Kingdom Hearts III leans clearly harder on optimization.
Grand Theft Auto V
Heists, money loops, builds learnable.
Kingdom Hearts III
Attraction commands or boss study both solvable
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.