[watwut]

I know plenty of socially competent programmers who are also good programmers.

However, some people really do associate lacking social skills with technical skills. That sometimes informs company culture - be it by peefering to hire more stereotyped people or by creating culture where unnecessary confrontational style wins the day. In such culture people who have good social skill adjust the way they communicate (full disclosure: I personally did through I am not claiming super superior communication).