A Reddit user reported on a recent CD Projekt Red community event held in Warsaw, where the developer of the highly expected Cyberpunk 2077 (and highly acclaimed The Witcher 3) expanded on their latest cyberpunk game's story. According to CD Projekt Red, Cyberpunk 2077 will have a shorter main storyline than that of The Witcher 3, albeit its sidequests will be much more complex and impactful regarding the entire experience. With the Witcher 3 and its numerous sidequests taking north of 120 hours to fully complete (at least at this editor's pace), this might still place the game's playtime above that of The Witcher 3, depending on the number and complexity of said sidequests.
According to the user, CD Projekt Red in the community event said that The Witcher 3 sidequests were designed as branching events from the main storyline, which would then, sometimes, make it back onto the main storyline with some repercussions. However, Cyberpunk 2077 sidequests are being developed so as to then enable more of them to be generated upon completion, depending on choices made during that slight deviation from the main story, with most of them having some kind of impact on one another.