The development of GTA 6 is "chaotic," and has been subject to multiple reboots, according to a Rockstar leaker.
In recent videos (translated from French, via NeoGAF), Rockstar Mag reporter Chris Klippel, spoke at length about the game's development, which he said is "just a big mess really. I can tell you it has been confirmed to me - and I can't go into details - to date it is Rockstar's most chaotic project since its creation."
Citing the development difficulties suffered by Red Dead Redemption 2 and GTA 4, Klippel said that "next to this, that's nothing."
The issues appear to stem from multiple changes at the 'scenario level' - features like the game's narrative, characters, setting, and map. Klippel says that Rockstar has changed GTA 6 at this level "several times since 2014," including one reboot in 2019, despite a reveal initially planned for Spring 2020. Those large-scale changes make it difficult for either Rockstar or leakers to disseminate accurate information, as details are changing all the time.
Some of the development difficulties appear to relate to the departure of Rockstar co-founder Dan Houser last year. Klippel says that his withdrawal from the project was "not trivial," and may have resulted in or been linked to a reboot of its own.
Rockstar does appear to have given itself plenty of time to pull its next game together, with some reports suggesting it's planning to release GTA 6 as late as 2025. If the game's scenario was only locked down last year, that could certainly be necessary.
Klippel also reported that a Red Dead Redemption remaster is in development, and could be coming to PC.