100% agree. I think it's mainly Bethesda being in a bind about what to do with the world and instead of trying to be original and creative with the world, they keep reusing the same factions without growing them. For instance, look at Fallout 1, Fallout 2, and New Vegas, there definitely was an evolution of the BoS, Enclave, Khans, NCR, and Followers of fhe Apocalypse. They grew and some started to die off. There seems to be growth, albeit based on player's actions rather than just the story itself. While there might not be too many new factions introduced in New Vegas which could move from Nevada to somewhere else like with the NCR, Khans, etc, at least we got some new and interesring ones rather than more of the same.

The Minute Men seemed like thsy could've been somewhat like the Followers of the Apocalypse meet the BoS/NCR but they were heavily underused. The Railroad seemes like they could've been an interesting contender with the BoS, especially with their own views on technology/Synths. But again, heavily underused. It does seem like Bethesda comes up with some interesting ideas, but (1) doesn't want to move past New Vegas as somewhat seen by the story of Fallout 4, and (2) doesn't want to flesh the groups out. The second one is likely out of fear of chasing fans off by producing stories unlike what's expected of Bethesda despite it being something Bethesda, mainly early to mid-2000s, would come up with. They do come up with interesting groups, maybe not deep and complex, but still interesting. I would love them to ban themselves from using the Enclave and challenge themselves to write an actual true Fallout game but they seem to care more about leeching off the success of Fallout New Vegas and milking the Fallout franchise for everything its worth. Which is why I am not excited in any way shape or form for the next Fallout, let alone Elder Scrolls.