head to head
Total War: Warhammer III asks more than Fallout: New Vegas, and the gap is reads.

Optimization · Pure Optimization
A faction-driven RPG-shooter where build and route planning shape every ending.

Optimization · Pure Optimization
A campaign strategy game where army composition meets real-time micro.
Fallout: New Vegas leans Optimization (Pure Optimization); Total War: Warhammer III leans Optimization (Pure Optimization).
Fallout: New Vegas leans a little harder on execution, though the gap is small.
Fallout: New Vegas
Shooter inputs with VATS assist
Total War: Warhammer III
Real-time micro of units rewards quick hands.
Total War: Warhammer III leans clearly harder on reads.
Fallout: New Vegas
Scripted factions and enemies
Total War: Warhammer III
Campaign AI scripted; multiplayer battles adapt.
Total War: Warhammer III leans clearly harder on variance.
Fallout: New Vegas
Some loot and crit RNG
Total War: Warhammer III
Campaign events and battle terrain vary.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Fallout: New Vegas
Faction routing, perks, builds heavily rewarded
Total War: Warhammer III
Army comp, magic, and campaign economy 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.