It presents a future in 2022 that seems unlikely not because we're not currently on the verge of some great
ecological disaster, but because rough math suggests that the Heston character would've been born the year before the film's 1973 release and thus his declaration that he'd never seen a grapefruit (or grass, or cows) should worm its way into the audience consciousness as Soylent Green's statement that it's not serious, thoughtful science - fiction, but rather soapbox and screed timed to coincide with, in 1972, the
first international conference on climate change.