It's more that people who think they have a small dick try to compensate that with extremely "manly" behavior. They are the ones who reduce men to site of their dick as their main quality.
Small dick is a metaphor for a small ego, because those people think that women are only interested in well hung, successful, rich, powerful tall man.
Small dick is a metaphor for a small ego, because those people think that women are only interested in well hung, successful, rich, powerful tall man.