The red dot has only been removed from the minimap in recent Call of Duty games, and even this one. They're only visible when players aim their rifles in one of three situations.
Despite the change, players can still see the red dots whenever a UAV scan is underway, however, gunshots no longer show the enemies' red dots. Players can now shoot their weapons without being scared to reveal their positions, but not the exact location, unlike in Modern Warfare II.
Many players, like the one in the above tweet, treat the game like an arena shooter (which, to be fair, it kinda is). This significantly slows down the gameplay, and forces players to actively look for their enemies. In contrast, in Counter-Strike: Global Offensive or Rainbow Six Siege, players prefer playing tactically.
Not everyone is enraged by the lack of a red dot in the game. Sadly, these players are a minority, overpowered by the louder fans. Infinity Ward, on the other hand, shows no signs of retaliating against the minimap change.
Click here to learn more about the new features introduced in Modern Warfare II.