This is actually not the first time that there has been speculation regarding Modern Warfare 4. A couple of months ago voice actor Craig Fairbrass seemed to have listed four different Modern Warfare games on his Twitter bio, leading to speculation that he might have accidentally revealed that a fourth Modern Warfare title is in the works.
Fairbrass took to Twitter to try and dispel the rumors, indicating that the fourth Modern Warfare game he worked on was Modern Warfare Remastered, but as Gaming INTEL points out, the game is essentially a reworking of the original and wouldn’t need new voice acting, right? Their sources have also suggested that unlike Black Ops 4 which has done away with the single-player campaign, Modern Warfare 4 is expected to come with it, and that a Battle Royale mode is also being considered.
It has been about 7 years since the release of Modern Warfare 3 so we guess the series is long overdue for a new game, so it’s not exactly surprising if Modern Warfare 4 is indeed in the works, but since this is a rumor, it’s probably best to take it with a grain of salt for now.