The area where I can see a VC's network adding a lot of value is 'person who built sales operation for growth company in related market'. That's not necessarily someone that's easy for a startup to hire, especially pre-Series A. On the other hand anyone if someone's output is aspirational pitch decks and market-scoping, at least one of the founders is already good at that to have got the VC interested, and by the time a startup's challenge is scaling operations the startup has cash to pay for the expertise.