Introvert-extrovert is a spectrum. The false dichotomy is that extroverts is not entertained by programming and/or other intellectual ventures.

It is simply a preconceived notion without any real evidence, much like the one that people wearing glasses is more intellectual than others.

There are good and bad programmers among both extroverts and introverts. I know a few introverts might wish things to be different, but there is simply no evidence at all for this. If you are to have an intellectual discussion about these things you have to let go of your preconceptions.