There is no VC who would have accepted a pre-SpaceX pitch for low cost launches, Starlink, or any of the rest of it. It would have been straight up "lol Iridium amirite, get out."
SpaceX was funded by Elon Musk and later, Draper Fisher Jurvetson and Peter Thiel's Founder's Fund. Starlink has been in part funded by a $1 billion investment from Google and Fidelity. And since then further funding rounds have been raised.
The DFJ and Founder's Fund investment was before SpaceX had any substantial NASA development contracts, let along their 2008 $1.6 billion launch contract.
Until the Dragon demo flights in 2012-2013, I think SpaceX would have been hard pressed to raise significant capital from anyone other than Elon's friends. I think the fact that so many private space companies have one or more wealthy benefactors bears this out (Blue Origin, Virgin Galactic, Armadillo to a lesser extent).
In 2020, SpaceX did 26 launches. Only six of those had NASA as a customer. The rest were a mix of US military, commercial customers, foreign governments (Argentina and South Korea), and Starlink. Even if you add up NASA and US military, that's still only nine out of 26 with the US government as the customer.
So while no doubt SpaceX does benefit from NASA's business, it is now only a minority.