This site is about refining the art of human rationality, while we certainly do try to get a good map of the world we spend most of our time thinking about thinking. The fundamental realization at the heart of our community, that to a certain extent distinguishes it from traditional rationality, is that humans are biased and broken thinkers who can't rely on their naive reasoning too much. You can think as long and as calmly as you like but if you base your thinking on broken axioms or bad epistemology you won't get much closer to truth.

I did not say or even wish to imply a set of arguments was wrong because of political affiliation, neither where the users I linked to. What I was implying quite strongly is that we are unlikely to hear the best arguments or to update appropriately to those that are politically inconvenient. Not even because of a desire to engage in propaganda for ones cause, but because the world simply looks a certain way to them! There are many correct arguments one can make for incorrect positions, by selectively only hearing correct arguments one does not by default hear the counter-arguments or correct arguments for other positions and perhaps doesn't' even realize they may exist. These are not a controversial observations at all.

Following this reasoning and promoted by complaints and observations observations of my own I stated my argument by pointing out the dominant political affiliation and ideological assumptions on the site and how this harms the rationality of the community on certain subjects.

This rationality quote by Jonathan Haidt may explain this better than I have. Also here is me making an argument explicitly along those lines.