Why?
Why do so many people who are extremely smart have no soft skills?
Well, I can't answer for anyone else, but it is a totally different mindset than "being smart". As the course discussed, one can have a high IQ and a low EQ since the two are not in any way equivalent. I suspect they use different parts of the brain. (Actually there are about 9 or so different ways to measure intelligence, including music and art. It really depends on one's society--most modern people would starve to death if they needed to hunt or grow their own food. Until they learned how to do it, they would seem very stupid to people who depended on such skills to survive.)
In my own case I have Asperger's, which means I'm functionally illiterate to body language, tone of voice, or subtle facial changes, not to mention telltale signs that someone is becoming angry...which has led to a lot of trouble, lost careers, etc. And I have 2 master's and a doctorate (not that degrees mean you're smart, just persistent). In the last decade therapists have taught me how to at least pass for "normal" and try to adjust to a society that always seems like a foreign country full of land mines, but it has never been easy. I envy people like sales folk or politicians who somehow intuitively seem to know how to read people. But on the other hand such an outlook can be useful (in at least a technical way) in engineering or the sciences. Focus, you know.
Anyway, hope that answers your question a bit.
This isn't actually the case. I think those people just stand out in our memory a little more. Research has shown the people with high IQ's tend to be over all more successful in all areas of life than those with low IQ's. However, there are cases of individuals with Autism or Aspergers as mentioned that are highly intelligent, but have difficulty reading emotions. Women also tend to have better interpersonal skills than men, but this is not always the case.
I think it depends on how high you're talking about. I do think there is a relationship between High IQ (Let's use upwards of 128) and Low EQ. I think part of it is because people with higher IQs spend more time reading/studying. Higher IQ children often simply spend more time with books and adults than with other children. I do realize, of course, that this is a generalization. Also, many highly intelligent people frequently reach a point in life where they become aware that there is something "off" about their social skills, and they study soft skills in much the same way they study anything else, and then they seek to change their behaviors (as much as possible) to become more socially acceptable.
People without soft skills aren't too smart...