head to head
Neither is simply harder - they are hard in different places. Grand Theft Auto V demands more reads; Resogun demands more execution.

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

Execution · Practiced Mastery
A voxel-based arcade shooter where precise movement and optimal human-rescue sequencing drive score.
Grand Theft Auto V leans Execution (Practiced Mastery); Resogun leans Execution (Practiced Mastery).
Resogun leans clearly harder on execution.
Grand Theft Auto V
Driving and shooting demand decent inputs.
Resogun
Precise overdrive timing and bullet-threading at high speed
Grand Theft Auto V leans clearly harder on reads.
Grand Theft Auto V
Online PvP exists but mostly gear/positioning, not modeling.
Resogun
Scripted enemy formations only
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Grand Theft Auto V
Some mission and lobby randomness.
Resogun
Particle-based destruction and some randomised enemy entry points
Resogun leans clearly harder on optimization.
Grand Theft Auto V
Heists, money loops, builds learnable.
Resogun
Keeper rescue sequencing and phase timing are fully 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.