If you're going to sink time into writing a book, it's worth spending some time editing it so your message gets through clearly. But that's just my opinion, your mileage may vary.
It corrects spelling errors and improves awkward wording. You can then go and choose alternative sentences or words. Just don't expect any sort of deeper intelligence.
The problem is: viewed as a one-off, it’s a gem. But put it on the AI slop conveyor many commenters here apparently are fed all day long, the voice is too similar, it seems like another chapter in that anthology.