head to head
Neither is simply harder - they are hard in different places. Driver: Parallel Lines demands more execution; Grand Theft Auto: San Andreas demands more optimization.

Execution · Practiced Mastery
Car-control execution through scripted chase missions and learned city routes.

Optimization · Practiced Mastery
A sprawling open-world crime epic with RPG-style character stats across a whole state.
Driver: Parallel Lines leans Execution (Practiced Mastery); Grand Theft Auto: San Andreas leans Optimization (Practiced Mastery).
Driver: Parallel Lines leans clearly harder on execution.
Driver: Parallel Lines
Chase driving and tight escapes demand solid car control
Grand Theft Auto: San Andreas
Flying school and drive-bys need decent hands
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Driver: Parallel Lines
Police AI follows predictable scripted pursuit logic
Grand Theft Auto: San Andreas
Gang AI is scripted, never adaptive
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Driver: Parallel Lines
Traffic adds light noise to chases
Grand Theft Auto: San Andreas
Territory wars and traffic add light randomness
Grand Theft Auto: San Andreas leans clearly harder on optimization.
Driver: Parallel Lines
Route knowledge and car upgrades smooth missions
Grand Theft Auto: San Andreas
Stats, gym, weapon skill, and routes reward systematic play
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.