head to head
Tony Hawk's Proving Ground asks more than Grand Theft Auto V, and the gap is execution.

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

Execution · Practiced Mastery
Combo execution and line routing through fixed skateparks for maximum score.
Grand Theft Auto V leans Execution (Practiced Mastery); Tony Hawk's Proving Ground leans Execution (Practiced Mastery).
Tony Hawk's Proving Ground leans clearly harder on execution.
Grand Theft Auto V
Driving and shooting demand decent inputs.
Tony Hawk's Proving Ground
Perfect inputs chain manuals, grinds and Nail-the-Trick combos indefinitely
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.
Tony Hawk's Proving Ground
Multiplayer score battles barely involve predicting opponents
Grand Theft Auto V leans a little harder on variance, though the gap is small.
Grand Theft Auto V
Some mission and lobby randomness.
Tony Hawk's Proving Ground
Skateparks are fixed and fully learnable
Tony Hawk's Proving Ground leans clearly harder on optimization.
Grand Theft Auto V
Heists, money loops, builds learnable.
Tony Hawk's Proving Ground
Routing the highest-scoring combo line through terrain is the meta
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.