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

Optimization · Pure Optimization
The original post-apocalyptic CRPG where character builds solve the wasteland.

Optimization · Pure Optimization
The original post-apocalyptic demon-fusing dungeon crawler where preparation and fusion knowledge decide survival.
Fallout leans Optimization (Pure Optimization); Shin Megami Tensei 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.
Fallout
Turn-based, no dexterity
Shin Megami Tensei
First-person menu battles; trivial inputs.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Fallout
No adaptive opposition
Shin Megami Tensei
Demon negotiation is random, not adaptive.
Shin Megami Tensei leans a little harder on variance, though the gap is small.
Fallout
To-hit rolls and random encounters
Shin Megami Tensei
Negotiation rolls, ambushes, and moon-phase RNG bite hard.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Fallout
SPECIAL builds and quest routing are deeply solvable
Shin Megami Tensei
Fusion charts, alignment routes, and weakness mapping are 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.