head to head
Call of Duty: Black Ops asks more than FIFA 21, and the gap is execution.

Execution · Competitive PvP
Cold War-era shooter pairing twitch multiplayer with the cult Zombies mode.

Execution · Competitive PvP
Football sim testing execution and opponent reading under a studied tactical meta.
Call of Duty: Black Ops leans Execution (Competitive PvP); FIFA 21 leans Execution (Competitive PvP).
Call of Duty: Black Ops leans clearly harder on execution.
Call of Duty: Black Ops
Gunfights hinge on aim and reaction speed
FIFA 21
Skill moves and finishing mechanics demand practiced hands
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Call of Duty: Black Ops
Reading human opponents' positioning and timing
FIFA 21
Outguessing a human's defensive shape and attacking patterns is central
FIFA 21 leans a little harder on variance, though the gap is small.
Call of Duty: Black Ops
Spawns, care packages, zombies RNG
FIFA 21
Deflections, finishing RNG and pack luck colour outcomes
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Call of Duty: Black Ops
Class builds, map control, zombies routing
FIFA 21
Meta formations, custom tactics and squad building are studied deeply
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.