...I think a far more possible scenario is Obsidian Entertainment stepping in...
Bethesda will never give Obsidian another chance after New Vegas. Todd Howard is still licking his wounds, a recent article has claimed.
This assumes it's solely for them to decide. Back then Obsidian also pitched a couple TES spin-offs to Bethesda. All declined. Given the lifetimes in between releases, Microsoft would probably step in and handle this differently now. With TES the same as with Fallout happened as well: Children that were made when Skyrim was born are attending high school soon. That's kids that have never experienced a single fresh main TES title in their life. Naturally also due to Bethesda not solely committing to TES. Still, Development cycles aren't going to big time come down anymore, even with the help of AI and ever improving tools.
Should both Avowed and TOW2 not meet expectations, it's far more likely that Obsidian are going to be turned into franchise juniors than them getting shut down either way -- like Tango Softworks or Arkane Austin were more recent. Whether that would be a good thing is another matter. The much smaller and more risky Pentiment I enjoyed far more than the likes of Outer Worlds as well. Mind you, I'm not expressing wishes. Rather, what appears more likely. To me even an inXile developed Fallout game seems more probable than one from Larian. First, they worked on Wasteland. Second, they also belong to Microsoft. And they also aim for the AAA-ish market with Clockwork Revolution now. A game that, just like Avowed and TOW2, is anything but a
guaranteed commercial hit.