I find the 'horror' there far more subtle; it's not the fright of sudden attacks by beasts that rend but more along the lines to me of such musings as 'why is that statue so lifelike' or 'what's down in that orchestra pit playing the music, is it just a concept of showmanship or something more sinister'. The sort of things which might unfold slowly, like a detective story, with subtle layers and twists. More psychological horror than the biological shock of sudden fright or fighting for your life, you might be 'fighting for your sanity' instead.
Vast separation of wealth and status, despair of poverty, a city of lights and manicured gardens crowned by ruins purposefully left in disrepair. I'd say the potential for very engaging, ongoing horror there is limitless but it's to me a very different sort of horror than what one might see in Barovia. More like Jack the Ripper, Doctor Jeckell and Mister Hyde, Herbert West Reanimator, Pickman's Model or Sherlock Holmes type stories but that was just my personal impression after spending weeks there wandering around.