This is very much true. Ghost writing is also done to keep the voice of the author, as much as possible. Doug Stanhope, notable comedian, drunk, and drug abuser, has a very entertaining book called Digging Up Mother. There’s no way he remembers all this stuff, and he admits it. But in the audiobook versions, he adds meta-asides that indicate when a name is fake, for example, or add a story that contextualizes something, or he’ll straight up say “I’m tired, so-and-so is taking over” and let someone else read, making it a much more authentic experience of how an “autobiography” comes together.