Some people were looking for less pozzed mod hosting sites than places like Nexus Mods. I came across this place:
I haven't gone through everything there but it does have, for example, "Hogwarts Legacy, Historically accurate 1800's Hogwarts," "WoW Wrath Classic Gender Icons," and FO4 Grounded Commonwealth.
If and when Starfield starts getting modded I am sure you can imagine what it will host.
The point isn't about the specific tech stack being used to make the game, the point is about the tools and extensibility.
Obviously it takes a lot of time & money for a game studio to develop the tech that handles these types of games, therefore only few developers try to do so.