What games have what you’d call really good worldbuilding, and what in particular do you like about them?
https://en.wikipedia.org/wiki/Worldbuilding
Worldbuilding is the process of constructing an imaginary world or setting, sometimes associated with a fictional universe. Developing the world with coherent qualities such as a history, geography, culture and ecology is a key task for many science fiction or fantasy writers. Worldbuilding often involves the creation of geography, a backstory, flora, fauna, inhabitants, technology, and often if writing speculative fiction, different peoples. This may include social customs as well as invented languages (often called conlangs) for the world.


Underrated because the game itself was often kind of lacking in terms of solid foundational RPG systems…
Arcanum: Of Steamworks and Magick Obscura
Pretty good attempt at putting a Middle Earth type world ahead a few hundred years in the midst of an Industrial Revolution.
Really thoughtful stuff like the labor exploitation of certain races like orcs, with quests like a half-orc you can help start a labor union or help the shop boss shut down the nascent union.