> Sure, but why do we have to conflate "disagreement" with "undesirability"?
Because most people find being challenged very tiresome and uncomfortable. People who are high in openness actually enjoy being challenged, but they are a minority (and it's definitely a spectrum).
I believe this, but there was also a time when it was considered a virtue to be more open-minded--calling someone "a literal Nazi" over some minor ideological disagreement (and then calling for them to be fired, attacked, etc) would have been roundly and correctly criticized. Now it seems like it's considered virtuous to exaggerate differences, police ideas, etc.
Because most people find being challenged very tiresome and uncomfortable. People who are high in openness actually enjoy being challenged, but they are a minority (and it's definitely a spectrum).