Cyberpunk 2077 Phantom Liberty was never going to take place after the main story: "The endings are written as we wanted them"

gamesradar.com:

CD Projekt Red never thought about developing an expansion set after Cyberpunk 2077’s multiple endings. 

That’s according to the game’s narrative director Igor Sarzyński, who tells PC Gamer that continuing the game’s main story would only cheapen the dramatic finales. “We did consider a couple of other scenarios,” explains Sarzyński, “but none of them were a continuation of the main game story.” 

Phantom Liberty’s position as a mid-game expansion came because CDPR was content with the base game’s conclusions. "The endings are written as we wanted them⁠ - leaving players with an uneasy feeling, forcing them to think, not providing straight answers,” Sarzyński continues. “They stick with you. No need to water them down. Sometimes less is more.” That approach seems to have paid off, based on the reception to Phantom Liberty and the 2.0 overhaul. 

But making a post-game expansion also posed a developmental challenge for the studio. Since Cyberpunk 2077 has a branching storyline with multiple endings, creating a single post-game expansion would essentially make one ending ‘canon’ and negate players' choices. “The endings are too diverse to have a single post-main story thread make sense for them all⁠,” Sarzyński explains, “and you don't want to pick one and invalidate other people's choices."

While CD Projekt Red didn’t elongate the base game’s story, the team did bolt on an additional ending with the release of Phantom Liberty. (Spoilers ahead!) “We always knew we wanted to add an ending in which V gets the cure and survives,” reveals Sarzyński, "but the cost of it had to be huge." That’s an understandable - if devastating - middle ground, I think. 

Phantom Liberty and the 2.0 update mark the end of Cyberpunk 2077’s