Well, it's a binary approach, to say that salvation is through Christ, the rest are damned. Or I should really say, dualistic, as with Zoroastrianism. It's not a coincidence that those against universalism, often talk about Satan, as they believe in a kind of dualistic universe, whereas universalists don't really. I suppose a lot of the New Testament is dualistic really, but I am not going to check! (By dualistic, I don't mean matter/mind, but God/Satan, or if you like, Ahura Mazda and Angra Mainyu (Zoroastrian)).