head to head
Neither is simply harder - they are hard in different places. Crash Bandicoot: On the Run! demands more optimization; Grand Theft Auto V demands more reads.

Optimization · Practiced Mastery
A mobile endless-runner spin-off of Crash Bandicoot with base-building elements.

Execution · Practiced Mastery
Sandbox crime playground spanning shooting, driving, and a persistent online economy.
Crash Bandicoot: On the Run! leans Optimization (Practiced Mastery); Grand Theft Auto V leans Execution (Practiced Mastery).
Grand Theft Auto V leans a little harder on execution, though the gap is small.
Crash Bandicoot: On the Run!
Timed swipes and dodges in endless-runner segments.
Grand Theft Auto V
Driving and shooting demand decent inputs.
Grand Theft Auto V leans clearly harder on reads.
Crash Bandicoot: On the Run!
No opposing player, purely solo runner mechanics.
Grand Theft Auto V
Online PvP exists but mostly gear/positioning, not modeling.
Crash Bandicoot: On the Run! leans a little harder on variance, though the gap is small.
Crash Bandicoot: On the Run!
Randomized run layouts and loot drops.
Grand Theft Auto V
Some mission and lobby randomness.
Crash Bandicoot: On the Run! leans clearly harder on optimization.
Crash Bandicoot: On the Run!
Base-building and resource optimization define long-term progress.
Grand Theft Auto V
Heists, money loops, builds 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.