head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Optimization · Pure Optimization
Post-apocalyptic city builder about balancing water, radiation, and morale against random disasters.

Optimization · Pure Optimization
The original post-apocalyptic CRPG where character builds solve the wasteland.
Endzone - A World Apart leans Optimization (Pure Optimization); Fallout leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Endzone - A World Apart
Pause-friendly mouse-driven management
Fallout
Turn-based, no dexterity
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Endzone - A World Apart
No adaptive opposition
Fallout
No adaptive opposition
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Endzone - A World Apart
Droughts, radiation, and raider events arrive semi-randomly
Fallout
To-hit rolls and random encounters
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Endzone - A World Apart
Resource chains and settlement layout are the whole game
Fallout
SPECIAL builds and quest routing are deeply solvable
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.