While PC Gamers' lack of love for the Call of Duty series has been well-documented, they seem to have a particular disdain, or at least a complete lack of interest, in 2016's entry, Call of Duty: Infinite Warfare.
Just a month ago, Infinite Warfare was routinely in the top 50 games played on Steam in terms of both current player count and peak player count on any given day. Today, it's dropped off the list entirely, meaning it doesn't have enough players to register in the top 100 most-played games.
Among many other titles, Infinite Warfare was beat out by several new games that only or at least primarily feature single-player, campaign-driven gameplay experiences, such as DOOM and Dishonored 2. These games don't automatically feature a reason to replay them, but are still getting more players than Infinite Warfare.
Because PC is hardly the premier platform for Call of Duty games nowadays, it's best to compare this with Call of Duty: Black Ops III, which is on the list, hovering around the 80th most-played game, with a peak today of 5,531 players.
This goes to show that something is particularly off-putting about Infinite Warfare as opposed to Call of Duty games in the past. This much is compounded by the game's disappointing sales and sub-optimal reception by both critics and audiences.