An engineer at SpaceX or Blue Origin is incentivized differently from one at JPL. SpaceX isn't designing rovers for a Titan mission or exploring novel theoretical propulsion systems. And NASA wasn't able to turn its decades of work on propulsive landing into a competitor to the Space Shuttle, Atlas or the SLS.
Note, too, that engineers at NASA are at the whim of Congress. I know several whose life work was cut in a budget negotiation thousands of miles away. I know several more who left aerospace for better pay in other industries.
Fair point, it does require the state to be willing to sufficiently and consistently invest in the effort for it to succeed.
That is not to say that then companies don't need to form around it, but not as black and white.
In other words, society needs more than just basic research and bureaucratic administration of basic government services.