Yeah it does take skill. Unfortunately, the game has become more newb friendly with each new iteration. UO was where the proper balance was struck. If you do well at the first CoD, it's because you understand the core mechanics of the game. Things like grenade launchers, custom classes, grenade indicators, kill streaks, and the mini map are just a lot of fluff which ultimately cripples the player.
It's an easy game to go positive with knifing and grenade launchers and luck and certain weapons. It takes skill to overcome those things. If you come out on top of a match using a G3 with a silencer and no stopping power, you're a lot more skilled than the player running around with a P90 in the green.