According to some rumors, Microsoft has opened a studio dedicated to remasters and remakes of Bethesda games and according to speculation the same could happen soon for Fallout, with a team dedicated to the franchise.
At the moment Fallout is developed by Bethesda Game Studios, the same team working on Starfield, The Elder Scrolls 6 and Fallout 76, by the Redmond house there may be the desire to make the development process more efficient by creating a dedicated studio , as happened in the case of 343 for Halo and The Coalition for Gears.
The reasoning seems simple: we know that The Elder Scrolls 6 will not go into active production until the team finishes work on Starfield and the expansions, this means that production will start at least in 2023 if not in 2024, with a hypothetical window launch internally set for 2027. At that point Bethesda Game Studios could also devote itself to the production of Starfield 2 and in this case Fallout 5 would still delay, ironically until 2035 jokes about Reddit.
This hypothesis apparently born from some reliable insiders with contacts in Obsidian and other Xbox studies was shared precisely on Reddit, it must be reiterated, however, as it is a speculation based on a logical reasoning but there is no concrete evidence to support. In all likelihood, Microsoft will make Fallout an increasingly important franchise in its IP catalog, and a dedicated team could help with the timing of the release of the games in the series.