Without Dan Simmons and Hyperion, sci-fi literature would've been still been regarded as disposable paperbacks. Simmons did away with the trappings of early pulp sci-fi that held a shadow over the genre for many decades. Instead, Hyperion and Fall of Hyperion took the shape of the Western Canon and could be discussed as serious literature. Without spoiling too much, I remember reading the story of Sol Weintraub and his daughter and almost being brought to tears; something that no other book, regardless of genre, has done.
Rest well, scribe. Asimov, Heinland, Clarke, Herbert and, of course, Keats. You'll be in good company