I was clearing out my self-storage locker recently; had to make room for some more junk. I came across a load of old books and magazines from the
1970s on the theme of anthropology and behavioural science. Much of it seemed to have come in the wake of Desmond Morris's groundbreaking works, Manwatching and The Naked Ape. There was quite a fad for this sort of thing in the early 70s, if you're old enough to recall, as I am, comfortably. So a lot of other authors jumped on the bandwagon. Anyway, I digress. One of the articles in one of these magazines stated that people with different political affiliations answer the question I posed differently and you can tell quite a lot about their political proclivities from the answers they give. There were dozens of examples but I just picked out one to reproduce here. It seems the term "insular" enjoys only pejorative interpretations to all. But the extent of that tells us much about those called upon to define the term. Liberal types are far more likely to see "insular" as a highly negative character trait. Nothing like so much, however, Conservatives. Liberals interpret the term to mean someone who is very rigid and outdated in their opinions; somewhat stuck in the past and unwilling to accept new ideas: narrow-minded, bigoted, blinkered and impervious to reason. Conservatives, OTOH, tend to define the term to mean a person who is merely somewhat withdrawn: aloof, reserved, cold, distant and somewhat unapproachable.
Looking down the list of uk.diy respondents to the original question, I'm inclined to believe the magazine article's assertion was pretty-much bang on the money, which is interesting. The way I see it is, Liberals see insular people as being too rigid and unyielding to bend to their modern ideas, whereas I for one (I doubt I'm alone) see it as Liberals being unable to mount a convincing enough argument or provide compelling enough evidence to convince others like myself of the virtues of the views they're trying to advance.
YMMV of course....