This was said in response to a question from a gamer who asked if Nuka World would be the last DLC or if Bethesda had plans for more later in the year, to which Hines replied by saying it would be the last one. However the upside is that Nuka World is expected to be a much more substantial DLC.
It is said to feature a new location and new story missions, meaning that unlike some of the game’s previous DLCs, it should last players a lot longer. The DLC is expected to be released in August and once that’s done, gamers should not expect Bethesda to be giving Fallout 4 that much more attention anymore.
Of course patches and bug fixes should continue to come as they arise, but like we said, in terms of new content this is it. However with the game supporting mods, we guess players will still find a way to have fun for many years to come.