Edit: Not to seem too negative, but I have just run into this attitude in most people that aren't introverts. There are advantages and disadvantages to both sides of that coin, but I feel like the introvert side gets labeled as the bad one.
In places like the US, extroversion is accepted and liked. However, in places like Germany, introversion is well respected and as an equal to extroversion.
I asked why and he said that he really didn't know. It's just the difference in culture.
The Introvert: introversion => social isolation => perceived snobbery => social challenges
The Nerd: socially challenged => social isolation => pretense of snobbery or introversion
There are introvert athletes and actors and musicians, but they're more popular in society. One of the quote-unquote coolest kids I know is a drummer who just never talks. He's incredibly shy. He smiles when people talk to him and says nothing, and for whatever reason people just absolutely love him. So introversion in and of itself isn't the issue.