ISF followed a rather familiar arc, starting out as a "private" company that was going to be independent of the government, and ending up trying to become a government contractor. Companies that successfully end up being a contractor then usually have a further step when they try to prevent other private companies from getting into the field. (It's called "rent seeking," where an established industry seeks to exclude new entrants.)
There are a lot of common steps in that arc too, such as starting out badmouthing the government program, claiming that their project is superior to the government one. Then they realize that there are not enough private customers to support them and most of the customers are government, so they change their position to say that they should get the government contracts instead of the government platform. And then there's often a step where they say that their proposal is not competitive with the government one, but complementary. (Often they have spent years badmouthing the government program, and now they want to partner with it, and this does not go well because they now need as allies the same people that they have been saying bad things about for years.) ISF's leadership wanted to do that by the early 1990s, arguing that they could be a free-flying platform that would be nearby the NASA space station. But nobody has come up with a strong need for a free-flying platform.
There are other examples of companies or organizations following this arc. You could put the B612 Foundation in the same category: for years they claimed they were going to fund themselves privately and they quietly badmouthed JPL's NEOCam proposal. Then they wanted government money to build their spacecraft.