Bethesda considered adding multiplayer to Fallout 4 but put the idea on hold to prioritize its singleplayer story, Bethesda Game Studios director Todd Howard explained in a new Noclip documentary. However, Bethesda eventually revisited Fallout 4's would-be multiplayer and turned it into Fallout 76, which we now know to be an online survival game.
"Fallout 76 is the multiplayer design from Fallout 4," Howard said. While developing Fallout 4, Bethesda wondered: "Hey, should we do multiplayer? 'Probably not.' What would it be? 'OK, it would be this.' Let's talk it through. 'OK, that's pretty awesome.'"
But at the time, the team decided to stick with its singleplayer focus: "Then we put it away, you know, let's do our thing," Howard said. "Then every once in a while we'd keep talking about it. 'We should've done that, we should do it.' And as Fallout 4's going on, it becomes 'no, we should really do it as its own thing.'"
As journalist and narrator Danny O'Dwyer explained in the documentary, Bethesda was experimenting with multiplayer Fallout as early as 2013. However, the studio didn't have many people experienced with multiplayer development. That changed when Zenimax, Bethesda's parent company, opened a new studio in Austin, Texas—Battlecry Studios, which was recently rebranded as Bethesda Game Studios Austin.
Battlecry brought MMO experts like Chris Mayer (Ultima Online, Star Wars: Galaxies) and Doug Mellencamp (Star Wars: The Old Republic), people who had the knowledge and contacts necessary to build a multiplayer Fallout. In fact, Howard said, "they started it before we shipped Fallout 4."