Developer MachineGames may have hinted at the arrival of a game that would be called Quake 6.
The hint is in the Developer Direct stream this weekend. At about 42:44 you can see a whiteboard with ‘ake 6’ on it, like that Acrymonia posted on Reddit. Four games have been released so far with the official count and no Quake 5 yet. Furthermore, it is not known whether the game will actually come.