The big sales may be the reason there's no sequel in the near future.
The gap between the release of Grand Theft Auto V and its likely sequel has now become the longest ever between two GTAs. The reason why, according to Strauss Zelnick, the CEO of Take-Two Interactive (who own Rockstar and 2K Games, among others), is that the game is still selling so well that they don't need to make a new one. Why would they? Five years after its release GTA V is inching ever closer to the 100 million mark. People continue to buy new copies of the game and also to play the online version of it, which is updated frequently. The most recent update is called "After Hours" and features the return of GTA IV's Gay Tony.
Zelnick admits that this trend isn't limited to Grand Theft Auto. He says that the release cycle of video games is being drawn out in general, with more ways for developers to update games and engage with players between releases, like the aforementioned "After Hours" or Fortnite's model, where all the transactions happen in the actual game.
However, big releases are still anticipated and Rockstar has another one of its biggest titles coming back with a sequel in October: Red Dead Redemption 2. The open world of the first Red Dead was a joy just to walk through and look at, never mind near-perfect story and zombie DLC and the new one looks to be no different. Watch the interview below: