Things have changed a lot since the late twentieth century. The kind of people you imagine, who can live full-time off writing, are responsible for a vanishingly small amount of the books that appear today. Piracy has little to do with it; this is primarily due to the fierce competition from other books, the glut of content available today, but especially from mobile phones as fewer and fewer people read books. Even for those who make appreciable income off books, the books are nevertheless usually a side gig alongside other hustles.