Sure, it's a little scary to think you could easily end up at a university like that (assuming you're brilliant)... but the PhD students I know at my school are not downtrodden or mentally abused. In fact, the one working in my lab seems relatively content with his lot in life, as long as it doesn't drag on too long, and his cohort seems to largely be the same. Yes they put in long hours, and they work hard, but as far as I can tell, they're far from being destroyed. The professors are collaborative, and seem to treat their students pretty well. Maybe this less abusive model isn't a common situation, but I see it, and I know it exists.