My own impressions. I've read LW regularly since it existed and I believe few posts describe a topic where there are mostly two opposite opinions or options. I haven't done a quantitative analysis.

There are also LW (and allied) posts that argue such situations are abnormal, and usually come about due to motivated reasoning (including politics) or fallacies and biases. And I believe LWers mostly accept this and follow this approach. For instance, the posts related to color politics argue this point.