Just kidding, but it's clear what the intent is here.
Even if you plan to devote your entire career to honing technical skills, the work around marketing one's self is also worth developing at least a little bit. It'll make it easier to position yourself in a community and to help others understand your ideas.
The extent of socializing that should be “learned” is recognizing things that may be confusing or upsetting. Nothing more. But by god and by no means should it ever be learning to act cool and by god not learning to lie about yourself. Those are extremely antisocial behaviors.
You generally get those skills from working at BigCo Inc.
While you can read books about them and apply them more successfully than someone who didn't read, you still need raw experience to move on from a beginner.
There should be plenty of positions at BigCo Inc. that are only looking for technical skills. Everyone has to start somewhere.