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.

Hyperion was pretty good, but the 70s New Wave of science fiction had already done that: Ursula K. Le Guin, J. G. Ballard, Samuel Delany, etc. They deserve their credit.