DCEU producer Peter Safran says James Gunn's The Suicide Squad is a "total reboot" of the franchise and not really a sequel to David Ayer's movie. Ayer's Suicide Squad was the third entry in DC's cinematic universe (following Man of Steel and Batman V Superman), but the first to focus on lesser-known comic book characters, with the exception of Harley Quinn. The DCEU movie went on to become a commercial success despite the relative obscurity of its source material, taking in $747 million at the global box office against a $175 million budget.
At the same time, Suicide Squad was poorly received by critics and Ayer declined to return for Suicide Squad 2. The project subsequently went through a few changes in creative personnel, before it landed in Guardians of the Galaxy filmmaker and newly-reinstated Guardians of the Galaxy 3 director Gunn's lap last October. However, from the get-go, Gunn's idea for the film was described by DC as a "completely fresh take" on the antihero property, and has since been officially dubbed The Suicide Squad, not Suicide Squad 2.
"First of all, we don’t call it Suicide Squad 2 ‘cause it’s a total reboot, so it’s The Suicide Squad and I think people should be extremely excited about it. It’s everything you would hope from a James Gunn script and I think that says a lot and that promises a lot and I know that we will deliver a lot."
While it might not be a sequel, Gunn's The Suicide Squad won't be a hard reboot either. The film is bringing back Deadshot from Ayer's DCEU movie, only with Idris Elba taking over the role from Will Smith (who had to drop out due to a scheduling conflict). It's also been reported that Margot Robbie will reprise her role as Harley Quinn in the sequel, following her second turn as the character in Birds of Prey (And the Fantabulous Emancipation of One Harley Quinn). Beyond that, The Suicide Squad will supposedly feature a whole new character roster, so it's not unreasonable to argue that the film is more reboot than sequel, as Safran has.
Some fans are theorizing that Gunn plans to kill most of The Suicide Squad in his film and is stacking the film's team with unknowns (as far as mainstream audiences are concerned), for related reasons. Indeed, one of the complaints about Ayer's Suicide Squad was that its titular "Skwad" didn't really live up to its name, as ultimately only Slipknot (who barely had any screen time) and El Diablo bit the dust. If Gunn's idea for "rebooting" the series is to really lean into the idea of a team of bad guys going on missions that will most likely get them killed, then it's definitely an exciting one that we can get behind.