head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is execution, and it is a single point.

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

Optimization · Practiced Mastery
A PSP-born GTA prequel adding a business empire system to 1984 Vice City.
Grand Theft Auto: San Andreas leans Optimization (Practiced Mastery); Grand Theft Auto: Vice City Stories leans Optimization (Practiced Mastery).
Grand Theft Auto: Vice City Stories leans a little harder on execution, though the gap is small.
Grand Theft Auto: San Andreas
Flying school and drive-bys need decent hands
Grand Theft Auto: Vice City Stories
Driving, aiming, and helicopter handling on a stick
Grand Theft Auto: Vice City Stories leans a little harder on reads, though the gap is small.
Grand Theft Auto: San Andreas
Gang AI is scripted, never adaptive
Grand Theft Auto: Vice City Stories
Mission enemies are scripted and predictable
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Grand Theft Auto: San Andreas
Territory wars and traffic add light randomness
Grand Theft Auto: Vice City Stories
Mostly fixed missions with light traffic randomness
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Grand Theft Auto: San Andreas
Stats, gym, weapon skill, and routes reward systematic play
Grand Theft Auto: Vice City Stories
Empire-building business system layers economy onto missions
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.