For your question, the difference is if a government spend succeeds, it should lead to more things that the people can do. If a private company succeeds, it largely funds just the company.
And, ideally, it should be fine that both the government/nation gets benefits while rewarding successful contractors. Nothing wrong with that.
This is hilariously viewable with Musk. People love to point out how he risked so much on Tesla. Ignoring all of the capital that the government risked in the same venture.