It's no secret that Activision plans its Call of Duty games years ahead. Unlike EA, Activision has continued with its three-year CoD development cycle, albeit with a slight changes. For example, it's Sledgehammer Games' turn this year instead of Infinity Ward. Treyarch stepped in to spearhead Call of Duty: Black Ops - Cold War back in 2020 after already working on Black Ops 4 in 2018.
With Treyarch's turn in the captain's seat due until 2023 at the earliest, audiences will get a chance to play at least two new Call of Duty games before then. There's Sledgehammer's Call of Duty: Vanguard that is scheduled for later this year. Then, there's Infinity Ward's next Call of Duty game in 2022.
However, even though Treyarch's next Call of Duty game isn't coming for at least the next two years, it appears that details about the unannounced game have leaked already.