This is something you really can't say one way or the other.
I could cite examples of sick, failing government owned companies that did better under privatization, or simply shouldn't have been governments owned in the first place. On the other hand, I could cite disastrous privatization efforts that should never have happened because they were vital services, or in the national interest. I lived through most of it in the UK when they were privatising stuff left right and centre - some succeeded, others didn't.
And if they stay under the control of government then they need incentivization and means for measuring success. Success doesn't just mean profit but it does mean value and quality of service. And in some ways that would require operating similar to if it were a private company.