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

Execution · Pure Mechanics
A fast-paced military shooter where twitch aim against other players is the core test.

Execution · Competitive PvP
Team-based WWII infantry shooter about holding and capturing map points.
Call of Duty: Vanguard leans Execution (Pure Mechanics); Day of Defeat: Source leans Execution (Competitive PvP).
Call of Duty: Vanguard leans a little harder on execution, though the gap is small.
Call of Duty: Vanguard
aim and reflexes decide most engagements
Day of Defeat: Source
Recoil control and snap aim decide most firefights
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Call of Duty: Vanguard
predicting human opponent positioning
Day of Defeat: Source
Human squads shift pushes and holds unpredictably
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Call of Duty: Vanguard
spawns and loadout drops vary
Day of Defeat: Source
Known maps, minimal randomness beyond spawn waves
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Call of Duty: Vanguard
loadout tuning and map knowledge help
Day of Defeat: Source
Class loadouts and lane control are quickly mapped
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.