It's long been maintained by GTA V fans that a proper single-player DLC/expansion never came because GTA Online became too much of a focus for Rockstar Games following its enormous and continued success over the years.
Now, at last, we have some sort of confirmation from former Rockstar camera artist Joe Rubino, who worked on Max Payne 3 and GTA V. In a video interview with YouTuber SanInPlay, he said:
A lot of the team went to do Red Dead Redemption 2 right away (after the launch of Grand Theft Auto V), and I kind of took on this other project that was a standalone DLC for Grand Theft Auto that never came out. That was my thing. I was one of the main editors and camera artists and did a lot of the on-stage stuff. We split our teams into two. I stayed on GTA Online and then this DLC, which Steven Ogg (the actor that played Trevor) was a very important part of.
Then some of the team overlapped and went to Red Dead Redemption 2 early on, and then we just kind of did this, because when that game got shelved, we spent so much money. A lot of that stuff, though, did end up making it, I believe, into later iterations of GTA Online. It's not like they wasted it. It was really, really good. What happened was when GTA Online came out, it was so much of a cash cow, and people were loving it so much that it was hard to make an argument that a standalone DLC would out-compete that. I think looking back now I would say that you could probably do both, you know? But that was a business decision that they made.
I was a little upset about that. Actually, a lot of the reason for me being a little sour at that time is that I was like, guys, this shit's awesome. Let's keep going, let's finish this. We went about probably halfway through it and then we put a pause on it because GTA Online was just so... People were going crazy (about it).
With Rockstar's resources, Rubino's point that
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