I suspect that the main reason for attitudes towards non-technical people is due to a wide distrust of "business type" guys. I think coders often have a great amount of respect for product designers, UI/UX folks making wireframes, .. or anyone who shows some capacity to actually make something, for deep thought & creativity, or to articulate a convincing & unique vision.
The greater myth is that "technical" people must lack "soft" skills. If you go beyond anecdotes, software engineers on the whole are more likely to be married & enjoy happy marriages, less likely to get divorced, have long lasting friendships, communicate honestly & care about others, are more likely to be engaged in politics and charities, etc. etc.
Likewise, engineering & building large software systems together (or any machine of complexity...), requires a great degree of communication & cooperation, thus it is no surprise that software engineers on the whole are actually pretty engaging people & have good communication skills.
The greater myth is that "technical" people must lack "soft" skills. If you go beyond anecdotes, software engineers on the whole are more likely to be married & enjoy happy marriages, less likely to get divorced, have long lasting friendships, communicate honestly & care about others, are more likely to be engaged in politics and charities, etc. etc.
Likewise, engineering & building large software systems together (or any machine of complexity...), requires a great degree of communication & cooperation, thus it is no surprise that software engineers on the whole are actually pretty engaging people & have good communication skills.