Why do you have this fixation that copyright has something to do with writing books? Copyright gives you (or your heirs - for 70 years, anyway) the right to control distribution of what you've
already written.
There's no difference between an author dieing, and a living author simply deciding to stop writing. His books still "live on", regardless of whether he's writing any more.
Look at that woman whose name entirely escapes me at the moment who wrote "To Kill a Mockingbird". She wrote that when she was young and (AFAIK) hasn't written another word since. She's lived on the income from sales of that book. By your argument, presumably she shouldn't be allowed to earn any money from it if she isn't writing any more?
