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 · Pure Optimization
Strategy sim about evolving a pathogen to outpace the world's cure effort.

Optimization · Pure Optimization
Optimizing regional economics and city services to sustain growth without collapsing your budget.
Plague Inc. leans Optimization (Pure Optimization); SimCity 4 leans Optimization (Pure Optimization).
SimCity 4 leans a little harder on execution, though the gap is small.
Plague Inc.
Tapping menus only
SimCity 4
Point-and-click placement; zero reflex requirement
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Plague Inc.
World response is algorithmic, not adaptive to you
SimCity 4
Solo sandbox with no adversarial pressure
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Plague Inc.
Spread events and cure pace fluctuate
SimCity 4
Neighbor city interactions and demand curves add unpredictability
SimCity 4 leans a little harder on optimization, though the gap is small.
Plague Inc.
Evolution-point timing strategies are largely solved
SimCity 4
Budget, ordinances, and transport networks are the core puzzle
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.