James Gunn, as you know by now, he was fired on the spot by the The Marvel movies even before shooting Guardians of the Galaxy 3.
The filmmaker has already found an opportunity to take revenge for the wrong he suffered: he was in fact hired by DC / Warner to write and direct Suicide Squad 2 which, apparently, will not be a direct sequel but a completely new story.
It remains to be seen whether, indeed, Gavin o'connor will be willing to leave the director's post to our James. Finally, remember that the break between Gunn and Marvel was born following some tweets (characterized by a humor that is nothing short of "controversial"), posted by the filmmaker almost eight years ago. Moral of the story: always pay close attention to what you write on social media ...