And if you go around killing things, yes, it will be lifeless. That's generally what happens when things die.
Markarth is pretty desolate after I busted out of jail and obliterated up a cannibal cult. It's pretty eerie, actually, and It feels like the Forsworn should come back in at any moment. I hope they realize that Calcemo and I aren't Nords, we bear them no malice, and are here for the Dwemer stuff. Their king could at least do that - I'd like it if I could side with the Forsworn in-game and reclaim Markarth.