Once you start playing the game, the level of detail used in generating the world is now used applied locally to simulating it. An example I like to use is to explain a bug where people's games were ending poorly (or with lots of FUN in dwarf fortress speak) because dwarfs were having mental breakdowns because their pet cats were dying. Which was because the game simulated the cats well enough that they could get alcohol poisoning and die. But why were the cats drinking that much alcohol? Because when they walked through dining rooms, the game simulated the dwarves getting drunk and spilling alcohol which stayed on the floor for some amount of time. If a cat walked over it, it got on their fur. When the cat cleaned themselves, which was also simulated, they would consume some of the alcohol on their fur. The bug was that each micro-dose of alcohol from licking themselves was accidentally being calculated like a full flagon of ale providing the small cat with far too much alcohol.
The level of the world generation with the level of simulation create a basis for a fantasy immersion that you cannot find elsewhere. The UI limitations, even with the steam version, do prevent most from becoming immersed into the world, but there seems to be a crowd who are brought in by the fidelity of the simulation and who can get past the UI that let's them experience something that cannot be found elsewhere.