I'm not sure that 'marginalising' is the right term but but I agree with the concept. Often, in attempt to be neutral there's a tendency to assign equal weight or validity to all points of view. This is often the case when you have an approximately 50/50 split (eg creationism/evolution in The States). But if you think that an objective truth exists (a right answer) to a fundamental moral/practical/scientific issue, it feels a lot like pandering.

A way to try & look at it from a position where you see something as this as an undeniable truth is to imagine a debate in a different time or place. Equal voting rights for women/minorities was once controversial in the US & Europe, How HIV infection occurs is controversial in some places currently. Would you be able to give equal time to all positions in these cases?