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

Execution · Practiced Mastery
Kart-style plane racing testing handling lines under item-pickup chaos.

Optimization · Practiced Mastery
A sprawling open-world crime epic with RPG-style character stats across a whole state.
Banjo-Pilot leans Execution (Practiced Mastery); Grand Theft Auto: San Andreas leans Optimization (Practiced Mastery).
Banjo-Pilot leans clearly harder on execution.
Banjo-Pilot
Plane handling and shortcut lines need steady GBA control
Grand Theft Auto: San Andreas
Flying school and drive-bys need decent hands
Banjo-Pilot leans clearly harder on reads.
Banjo-Pilot
Link-cable races add light human prediction
Grand Theft Auto: San Andreas
Gang AI is scripted, never adaptive
Banjo-Pilot leans a little harder on variance, though the gap is small.
Banjo-Pilot
Item pickups shuffle race outcomes
Grand Theft Auto: San Andreas
Territory wars and traffic add light randomness
Grand Theft Auto: San Andreas leans clearly harder on optimization.
Banjo-Pilot
Course knowledge and character choice settle quickly
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.