https://www.google.com/search?q=gwynne+starlink+profitable

And I listed a bunch of other things that also fund spacex. Starlink is only one part.

In addition to all the things I listed previously, they also sell spaceflights to civilians.

You're really rabbit holeing on one thing -- you're wrong about that but even if you're right the original statement STILL holds. SpaceX doesn't need nasa to get humans on mars, it just makes it easier.

Of course they aren't actually going to go to mars without nasa - nasa will get on board the SpaceX plan at some point - too embarrassing to get left behind. But SpaceX COULD

However, NASA cannot keep astronauts on the ISS full time without either SpaceX or Russia.