I’ve seen people talk about actors and artists that had a terrible time.
My own would be Anne Rice. She wrote Interview with the Vampire after her young daughter died of Leukemia. Then her husband suddenly died of a brain hemorrhage. I suspect her Christian, anti-fanfic phase was a result of mental illness and manipulation from the publishers, although I don’t think she ever apologized.
Even among compared to his contemporaries, he did quite poorly (at least, in America—for some reason, French people were his biggest fans during his lifetime). There were plenty of poor poets, but he really struggled just to stay at the bottom of the barrel. He also inspired other writers such as Ranpo who went on to popularize the detective fiction genre Poe originally started…but even then, many of his stories remained obscure for a long time even as his pupils achieved fame. When he died he was still unknown, Compared to now, when he and his works are practically the face of a major yearly holiday? I’d definitely say that counts as under appreciated.