Definitely, extraversion - especially amongst males - is highly desirable in American culture.

He actually argues that women are more pressured to be extroverted: "In certain circles, particularly in the Midwest, a man can still sometimes get away with being what they used to call a strong and silent type; introverted women, lacking that alternative, are even more likely than men to be perceived as timid, withdrawn, haughty." I guess coy and cutesy is one alternative ...