I _think_ the OP means "EQ", not "IQ", i.e. Emotional Quotient. Engineers certainly have a reputation of having lower EQ but I haven't seen this in practice. Just like any group of people there is going to be a range.
I can see how OP might have meant to write EQ. Oh well. I think overall, the days of stereotypical genius engineers lacking in social skills are mostly a thing of the past. People are on a social spectrum regardless of their technical skill.