It's Modern Warfare 2 and Modern Warfare 3 that drove the game away from allowing skilled players to beat unskilled players. Black Ops 2 took it to the extreme.
There aren't infinite restocking noob tubes in MW3 or BOII. MW3 and BOII have worse netcode than MW2. What does it matter how "skilled" you are at the most massively casual console shooter of all time when the other guy has a 250-500ms advantage over you? BOII doesn't have deathstreaks or a "Support Strike Package," is the least friendly CoD game to campers and increased the presence of the skill component in Public matchmaking.
So... where in this do you see the trend that MW2, MW3, and BOII allow unskilled players to defeat skilled ones when they're all fairly different?
"An Incandescent Revelation in a World of Darkened Forms" The bird of Hermes is my name, eating my wings to make me tame
Nope. It was MW2 for sure, but the game itself doesn't deserve full blame. It did a lot of stuff well and admittedly was very fun sometimes, but with plenty of help from the Youtube community it kicked off a strong focus on killstreaks which has basically poisoned the gameplay ever since, imo. The obsession with stats and performance, sense of entitlement surrounding streak rewards, and overall obnoxiousness of the community all started very strong with MW2.
Black Ops is actually my favorite in the series, as it accommodates my preferred playstyle very well and downplayed killstreaks compared to the other post-W@W titles. Sadly, I am confident that BO1 Domination will remain the all-time high point of the CoD franchise for me.
MW3 was a mess that I would prefer not to dwell on any more than I already have. I've heard it was cleaned up quite a bit several months in, but I haven't gone back. I feel very similarly about BO2 for the time being, despite it being excellent on paper.