head to head
Guild Wars 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
Instanced online RPG where deck-like eight-skill builds decide battles before they begin.
Fallout: New Vegas leans Optimization (Pure Optimization); Guild Wars 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: New Vegas
Shooter inputs with VATS assist
Guild Wars
Interrupt timing and kiting in skirmishes
Guild Wars leans clearly harder on reads.
Fallout: New Vegas
Scripted factions and enemies
Guild Wars
GvG and arena metagame against adapting humans
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Fallout: New Vegas
Some loot and crit RNG
Guild Wars
Modest drop and spawn randomness
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
Guild Wars
Eight-skill build construction is the game's soul
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.