She comes up with new stuff all the time. She's had a separate career as a writer of thrillers, and is still working in the PotterVerse.

She's an awful person for other reasons, but that's beside the point here.

Reality is most trad-pub authors have full-time jobs anyway to pay the bills. If you're not one of a handful of publishing superstars, trad-pub pays incredibly badly as a result of corporate consolidation and monopoly dominance.

To be clear - there are far more people living parasitically off investments, producing nothing at all and extracting value from everyone else, than there are talented creators living the high life.