head to head
Fallout: New Vegas asks more than 13 Sentinels: Aegis Rim, and the gap is execution.

Optimization · Pure Optimization
A sci-fi mystery that splits across thirteen protagonists' stories, backed by light real-time strategy battles.

Optimization · Pure Optimization
A faction-driven RPG-shooter where build and route planning shape every ending.
13 Sentinels: Aegis Rim leans Optimization (Pure Optimization); Fallout: New Vegas leans Optimization (Pure Optimization).
Fallout: New Vegas leans clearly harder on execution.
13 Sentinels: Aegis Rim
Real-time strategy battles have light unit-control inputs
Fallout: New Vegas
Shooter inputs with VATS assist
Fallout: New Vegas leans a little harder on reads, though the gap is small.
13 Sentinels: Aegis Rim
Kaiju wave patterns are scripted per stage
Fallout: New Vegas
Scripted factions and enemies
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
13 Sentinels: Aegis Rim
Hidden story order and mystery connections obscure the full picture
Fallout: New Vegas
Some loot and crit RNG
Fallout: New Vegas leans clearly harder on optimization.
13 Sentinels: Aegis Rim
Optimising battle chip builds and unlocking all story segments is the mechanical layer
Fallout: New Vegas
Faction routing, perks, builds heavily rewarded
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.