I think you could totally build something like Westworld today, of course not with the current real state of technology. Whether it would be practical, profitable, or ever actually made is another story, but nothing in it strikes me as impossible. What is more fascinating to me is the question of ethics that goes with the question of whether humans would ever knowingly create these kind of robots/androids. Beings that obviously experience actual physical and emotional pain when damaged, or at least are programmed to make an extremely good simulation of that. They are such good simulations that the average person can't tell the difference, in which case the makers are philosophically unable to really know whether these artificial people are really People, or just objects/things.