There are two (or more) layers of duality, the first is a false duality, that of good vs evil and right vs wrong, while the second is a polarization, the separation of the living from the dead, the spirited from the spiritless. Those without a spirit are able to manipulate the first layers of duality because they are neutral to it, they are outside and beyond it, while those with a spirit are able (if they have done their work) to integrate the false dualities into the One within, since they too are capable of neutrality, and thus can also be outside and beyond it. A neutral being is neutral to duality because they are not within the fractured belief structures that hold those inside of it prisoner. Unity beings are neutral to those in duality, but not to the spiritless and dead parasites, while the Dead are neutral to those in duality, but not to the unity beings that are busy integrating the false dualities back into One.
The struggle between the light vs dark is true, but those stuck in the false duality are not perceiving the world from the light vs dark perspective, they are still viewing it from within their prison, and are thus perceiving the false constructs meant to keep them imprisoned. Their light vs dark is just a re-branded good vs evil and right vs wrong, because they are incapable of moving beyond their own internal struggle. The actual light vs dark struggle is far beyond what their perception will allow them to see; they are merely parrots repeating the language of both the neutral parasites and the neutral unity beings, incapable of further awareness beyond their own limited perceptions. If they want to move beyond parroting those beings who are outside of duality, they will first need to understand their own dillusions and limiting patterns, and to the degree that they do understand why there are the way they are, they are able to move further and further into the truth and see things for how they really are, and not how they were programmed to see that they are.