Jason Bourne was... okay.
Kinda like The Bourne Supremacy in spending about as much time dealing with the conclusive ending of the previous film (not counting The Bourne Legacy) and going “hey, there’s another secret layer to deal with...”
And while the stunts were great, none of them were up to the “did you just see that?!” effect of Bourne jumping off a roof in through a window and the camera following him from The Bourne Ultimatum.
There’s also a whole lot of computer tracking sequences, as this Sight & Sound review notes.
So how does it follow that ending?
Partially by revealing another level of trouble, and partially by killing yet another person Bourne cares about. Two, in fact, one of whom appears here for the first time and only in flashbacks.
Dropping an extra layer into a conspiracy plot is fairly easy. Undoing a happy ending to start a sequel is also easy, but it’s always bothered me.
Personally for a “just when I thought I was out...” setup I would suggest bringing in a new problem that the retired hero feels a duty to tackle. (The Bourne Ultimatum does this, introducing a Guardian journalist in danger due to what he knows.)