What Jung meant by extroversion is not what's commonly known as extroversion today.
Today, what most people mean by an "extrovert" is someone who's very outgoing and social, while an "introvert" is typically seen as a shy loner.
But for Jung, who coined these terms, an extroverted person was one interested mostly in the world outside of himself, while an introvert was interested primarily on what was going on inside himself.
Jung would have seen no contradiction in introvert who was very gregarious and outgoing, if he was mostly interested in his inner world (since it would be the latter quality that made him an introvert).
Likewise, Jung would have seen no contradiction in extrovert who was very solitary and shy, if he was mostly interested in the world around him (since it would be the latter quality that made him an extrovert).
Now, as for whether this is a "myth" or not is a matter of opinion and debate. Psychology is far from a settled discipline, where all participants agree on the "great truths" like "the law of gravity" or "the laws of thermodynamics". There aren't any such things in psychology, since there are in fact many different psychologies, with radically different explanatory frameworks. What is a myth to one psychologist might well be established dogma to another.
Today, what most people mean by an "extrovert" is someone who's very outgoing and social, while an "introvert" is typically seen as a shy loner.
But for Jung, who coined these terms, an extroverted person was one interested mostly in the world outside of himself, while an introvert was interested primarily on what was going on inside himself.
Jung would have seen no contradiction in introvert who was very gregarious and outgoing, if he was mostly interested in his inner world (since it would be the latter quality that made him an introvert).
Likewise, Jung would have seen no contradiction in extrovert who was very solitary and shy, if he was mostly interested in the world around him (since it would be the latter quality that made him an extrovert).
Now, as for whether this is a "myth" or not is a matter of opinion and debate. Psychology is far from a settled discipline, where all participants agree on the "great truths" like "the law of gravity" or "the laws of thermodynamics". There aren't any such things in psychology, since there are in fact many different psychologies, with radically different explanatory frameworks. What is a myth to one psychologist might well be established dogma to another.