head to head
Call of Duty: Modern Warfare 2 asks more than WWF SmackDown!, and the gap is execution.

Execution · Competitive PvP
Blockbuster 2009 sequel famous for killstreak chains and frantic multiplayer.

Execution · Competitive PvP
Tests grapple timing and predicting an opponent's next move choice.
Call of Duty: Modern Warfare 2 leans Execution (Competitive PvP); WWF SmackDown! leans Execution (Competitive PvP).
Call of Duty: Modern Warfare 2 leans clearly harder on execution.
Call of Duty: Modern Warfare 2
Fast time-to-kill rewards raw aim and reflex
WWF SmackDown!
Grapple timing and reversal inputs decide exchanges
Call of Duty: Modern Warfare 2 leans a little harder on reads, though the gap is small.
Call of Duty: Modern Warfare 2
Outguessing human rotations and flanks
WWF SmackDown!
Against a friend, predicting grapple choices is the game
Call of Duty: Modern Warfare 2 leans a little harder on variance, though the gap is small.
Call of Duty: Modern Warfare 2
Spawn flips and killstreak randomness
WWF SmackDown!
Some reversal and AI randomness in season mode
Call of Duty: Modern Warfare 2 leans clearly harder on optimization.
Call of Duty: Modern Warfare 2
Killstreak economy, loadout and map knowledge
WWF SmackDown!
Move-set knowledge and stamina management are shallow but real
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.