head to head
Call of Duty: Modern Warfare 2 asks more than Worms Reloaded, and the gap is execution.

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

Execution · Competitive PvP
Artillery aim and turn planning against humans under wind and crate randomness.
Call of Duty: Modern Warfare 2 leans Execution (Competitive PvP); Worms Reloaded 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
Worms Reloaded
Grenade arcs and ninja-rope shots demand fine aim control
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
Worms Reloaded
Anticipating human opponents' target priorities shifts each turn
Worms Reloaded leans a little harder on variance, though the gap is small.
Call of Duty: Modern Warfare 2
Spawn flips and killstreak randomness
Worms Reloaded
Random terrain, crates and wind perturb every shot
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Call of Duty: Modern Warfare 2
Killstreak economy, loadout and map knowledge
Worms Reloaded
Weapon economy and positioning theory reward planning
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.