Also notice that the object of “to condemn” is “the world” — not “part of the world.” You’re trying to say that the context alters “the world” into “part of the world” — which seems a giant stretch at best. I say 3:17 remains true both alone and when viewed in light of 3:18. 3:18 is not speaking of any present role of Jesus except to sound a generalized warning.
Jesus is holding off on damning. Damnation is such a high voltage, emotionally and spiritually charged subject, that it is difficult to handle well. But unless it is handled well, it will likely get Christians in a perpetual mess of argument and, well... damning of one another.