Well, I think relegating libertarianism to insane lifeboat ethics is what interferes with the advancement of understanding. People only hear about these unlikely extremes and think that’s what libertarianism is. A libertarian society is always explored in the form of these unpleasant hypothetical situations around the edges. For example, everyone heard the “what about people who can’t afford food” problem, but really few people are aware how higher productiveness in a libertarian society would make food really abundant. Libertarians defend against the former, but they rarely point out the latter. For some reason the opposition managed to make all discussion about fringe circumstances under which libertarianism might conceivably be imperfect. And libertarians are too eager to follow the argument down that road. (My guess is because they like theorizing so much.) Libertarians never talk about the abundance and the ease of life that would be possible if we had free markets, we mostly complain about the current system; while the communists go on and on about superabundance and free stuff. Is it any surprise that the audience is inclined to support the more pleasant sounding ideology?
One time I had a person argue that free market economics “fails” because people don’t have perfect knowledge or act perfectly rational. In other words, if the theoretical optimum is unattainable then we better not risk it at all. There was no mention of whether this slightly imperfect situation is still better than the statist alternative. No, libertarianism is considered a failure if it is not perfect. People are much more lenient with statism for some reason. Yeah, it was the leading cause of unnatural death, but at least it’s not worse than the theoretical optimum!