Halo came out in 2001. Half Life 2 came out in 2004. Far Cry came out in 2004. Call of Duty 4: Modern Warfare came out in 2007. Far Cry 2 came out in 2008.
It’s tough to say, just because that sort of single player campaign FPS has gone away, for the most part. Instead, you have the super-linear Call of Duty series, that follows the Modern Warfare template ever since. The Halo games follow the Halo template, which has narrow corridors and wide corridors. The Far Cry games actually follow the Far Cry 2 template, in that they’re open worlds, not the “wide corridor” shooters like Halo and the original Far Cry. Some parts of Half Life 2 were also wider corridors like Halo/Far Cry. The Wolfenstein games follow the Halo/Half Life 2/Far Cry template, I would say. If you want to count 3rd person games, the Gears of War games are there, and they spawned a bunch of their own clones briefly.
But there’s not many AAA FPS games anymore. Am I missing something obvious? It’s just Wolfenstein, Far Cry and Call of Duty right? Only one of those (Wolfenstein) follows the Half Life 2 type gameplay I would say.