You are absolutely right in principle: networking (business-speak for "talking to people") is highly advantageous at all stages of one's career, nearly irrespective of field.
I'd clarify, though, that social skills are learnable to a large degree rather than exclusively an innate trait. I've found that those who stubbornly refuse to accept social skills as a valuable indicator of 'fitness' for employment/advancement are simply arrogant, immature, and/or suffer from a delusion of geek grandeur. Some of these people will go on to be extremely successful; others are content to wallow in envy and self-effacement. A key differentiating point is the time which the former group recognized accepted that relationships are necessary to accomplish something of value and put their effort into learning how to establishing those relationships.
There is no shortage of CEO's, actors, prominent scientists, or what-have-you, that describe their intense shyness and their efforts to overcome the detrimental effects to their career.