head to head
Onrush asks more than Grand Theft Auto: San Andreas, and the gap is reads.

Optimization · Practiced Mastery
A sprawling open-world crime epic with RPG-style character stats across a whole state.

Execution · Practiced Mastery
A team arcade racer with no finish line, scoring takedowns and objectives in a rolling stampede.
Grand Theft Auto: San Andreas leans Optimization (Practiced Mastery); Onrush leans Execution (Practiced Mastery).
Onrush leans clearly harder on execution.
Grand Theft Auto: San Andreas
Flying school and drive-bys need decent hands
Onrush
Boost management and aerial takedowns need car control
Onrush leans clearly harder on reads.
Grand Theft Auto: San Andreas
Gang AI is scripted, never adaptive
Onrush
Team-based human opponents in stampede modes
Onrush leans a little harder on variance, though the gap is small.
Grand Theft Auto: San Andreas
Territory wars and traffic add light randomness
Onrush
Chaotic pack collisions and fodder spawns
Grand Theft Auto: San Andreas leans a little harder on optimization, though the gap is small.
Grand Theft Auto: San Andreas
Stats, gym, weapon skill, and routes reward systematic play
Onrush
Class roles and rush timing are 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.