It looks like Call of Duty is just going to be known as "Call of Duty" going forward, as Activision Blizzard is rebranding Modern Warfare 2 and Warzone under a single, more generic header - at least on PC.
Across both Steam and Battle.net, the game client formerly known as Call of Duty: Modern Warfare 2 is now simply called Call of Duty. In an announcement on the Battle.net change, the devs say "this should make deploying to the battlefield even more straightforward, so you and your squad can worry less about where to launch and more about how to score your next victory."
