More clearly stated, you are operating under a non-disclosure agreement. That's understandable.
But in general, I believe that an author who uses a ghost writer, particularly when the result is a tangible work (book, article, etc.) published and sold under his/her name, and who doesn't reveal the ghost writer's contribution, is clearly being dishonest to anyone who might read that work.
The case of a political speechwriter is different, since it's widely known and assumed that politicians routinely farm out their speeches to contract writers.
When a ghost is involved, there is always the question as to whose thoughts you are actually reading, as you alluded to in your original comment about Trump's book, and that's a fair point to make.
But at least Trump is honest enough to disclose his ghost writers for most (if not all) of his books. And that's more than you can say for people like Barack Obama and Hillary Clinton.
I don’t disagree with any of what you said. FTR, unofficial record, my biggest and most significant ghost work was for on air commentary, humor, analogies, etc.