I can see two developments that might grab a wider readership for poetry. One would be a return of serious, sustained narrative poetry, but right now that is so unfashionable I can't conceive of anyone doing it. The second, and there's no reason why this could not happen, is that poets suddenly started to deal again, in powerful, fresh language, with the great issues of philosophy, religion and history in their verse. Eliot and Pound did it, and their poetry still smolders on the page. I don't think there's too much literary biography, although I'm not sure why so much of it does get published.
Most authors live pretty boring lives.
As a reader, I'd say a writer would have to have lived a very unusual and interesting life, or been extremely significant in the context of his or her times, for me to bother reading a biography of them. One of these days I might get around to reading the multi-volume biographies of George Bernard Shaw and Graham Greene that I have in my own library at home, but I think I would be painfully aware that in the amount of time I spent reading these I could be reading several Greene novels, instead. Obviously some literary biographies are very good at what they do. My own defence of my biography of McLuhan was that McLuhan was not much of a writer, he was a speaker, not a writer, and that his work badly needed translation into English and interpretation for a wider audience. But that's a special case.