Rinslin Merwind
Erudite
Y'know even after ten years on Steam with all the deep discounts, Bloodlines hasn't even broken a million copies http://steamspy.com/app/2600
Meanwhile, Deus Ex and Morrowind have over one million each http://steamspy.com/app/6910 http://steamspy.com/app/22320
So the problem isn't necessarily with mechanics or bugs, it's that most people have no interest in the setting/premise.
I am not sure how good Bloodlines, but it's not only about setting. Morrowind had better publishers (and still have) Ubisoft in Europe and Bethesda elsewhere (also Xbox version, can be played on Linux and Mac Os). Deus X have Mac OS and PS2 with PS3 versions and can be played through Wine on Linux. In result Deus X and Morrowind was available to more wide auditory than Bloodlines at release. People who had Deus X or Morrowind on console just bought it on PC. Also (if I am not mistaken) Morrowind had better marketing in general and even commercial on TV. But yeah, definitely not all people like vampire setting. Including myself, but i maybe this game worth it, I don't know.