Music is an extraordinary vehicle for expressing emotion - very powerful emotions. That's what draws millions of people towards it. And, um, I found myself always going for these darker places and - people identify with that. ↗
You want the book to be special, and they are not always going to be special, but at least you want that to be the ambition. So the only way that happens is if you are not pressing to write a book. ↗
There is also this benefit in brag, that the speaker is unconsciously expressing his own ideal. Humor him by all means, draw it all out, and hold him to it. ↗