I'd wager it's because of the step back the player takes from the actual world. Like, Dwarf Fortress adventure mode exists, but it gets tedious. Carefully decid

I'd wager it's because of the step back the player takes from the actual world. Like, Dwarf Fortress adventure mode exists, but it gets tedious. Carefully deciding which molar of your opponent to grab while grappling isn't the most engaging gameplay. But when you take a step back, and are making general instructions to your dwarves like "Go fight these goblins", the added complexity makes for some very memorable moments. Combine that with a gameplay loop that basically demands a sprawling amount of new things to do (since the dwarves basically handle themselves in the steady state), and you've got a recipe for some truly expansive games. Plus every modern game in the genre is directly inspired by Dwarf Fortress, who is made by someone who really seems like he just wanted a way to get people interested in his high fantasy world simulator.