1) You are quoting a study without giving references: who has done this study, when, how? It is always important to tell these details otherwise anyone with a little bit of imagination can throw any conclusions, saying that they "come" from a study. I am not saying that is not true, but this is how the things are done. *Now, you don't have to bring references, I believe you that it is true and maybe you don't want to say the name of the university where your friend is studying and is OK. I can totally understand you.
2) When you have first used the word "average", you didn't give any explanation in what context you are using the word and with what definition. Of course people went for the common use of the word and felt insulted, and you don't have any right to come later and say that they haven't understood you. It was your duty to clarify this in the first place if you wanted a healthy discussion.
3) When someone does a research in psychology/sociology, first they ask the permission of the subjects to study them. It's unethical from your part to quote an article and then to pass judgments on people here based on this study saying that they are "average". First of all you are not a psychologist and secondly people here haven't given you any right to study them and put them in a category. Is not only unethical, is not nice. I've studied sociology, how would you feel if out of the blue I am starting to analyze your social behavior on this forum quoting articles, books and theories? That's what I am saying that things like this should not be done.
4) And this one has nothing to do with you. I find the study quite judgmental itself. "Great minds" and "small minds" imply strong messages as they stand for intelligence and stupidity in the common language. Not so sure what they wanted to achieve with this, they could have gone for neutral words. It creates confusion. I feel like they want to glorify the western style of life while minimizing the people who don't follow this trend. Science should be neutral, and not judge a behavior being worse or better than the other. Anyway, I don't have the article so I can't comment more on it and is not the place to do so. I am not saying that it is wrong or that your friend is wrong, but the terms used don't seem well placed. I am going to search for other articles regarding this subject to see a second opinion as psychology/sociology are not maths and researchers have most of the times different theories to explain the same human behavior.
But, if we have to go into scientific debate to explain a simple TV show, then we are in more trouble than I first thought!
And whatever we are writing it doesn't change one thing: if you like the show it doesn't matter what other people are thinking and if you don't, no arguments in this world can make you change your mind.
P.S. Please, don't pass these type of judgments on people again, otherwise you will receive again many replies like these. It doesn't matter if you meant no harm. Just explain clearly what you want to say as no one wants to be name calling, you wouldn't want that either, don't you?