You have to be true to who you are.  Both introverts and extroverts can be successful leaders.  I believe there are just as many pitfalls for extroverts as there are for introverts.  An introvert can use his/her introvertism to their advantage.  Some Soldiers will respond better to leaders who are more reserved.  However, leaders need to engage with those around them.  Sometimes, though, people like to “engage” for hours during the day to avoid work.  Each leader needs to find a balance that works for them.

I think sometimes people are quick to put labels on others.  Some leaders are very analytic and prefer to analyze a situation before jumping in (when possible).  That can be a very useful tool and does not necessarily mean someone is an introvert.  Sometimes taking a step back can be the best thing to do.

I would agree that someone cannot completely cut themselves off of social interaction as a leader.    Likewise I would say someone who is an extreme extrovert may need to dial it back some.  The chain of command structure does not prevent leaders from interacting with anyone in their formations, but the structure can be eroded if leaders continually engage too often or become too friendly.  I think as long as leaders find a place away from the extreme ends of the extrovert introvert spectrum, they will be fine.  They need to recognize how their leadership style impacts the unit (positively and negatively) and adapt accordingly.