Children of Men to Blade Runner to V for Vendetta. The sub-genre that uses near-future settings to argue about the present.
Dystopian science fiction is the genre that takes a contemporary anxiety — environmental collapse, authoritarian government, technological dependency, social fragmentation — and projects it into a near future where the anxiety has become the social structure. The genre's best entries use the future as a thinking-tool about the present.
Almost every successful dystopian film uses one specific anxiety as its central conceit. Children of Men: infertility (and, by extension, civilisational continuity). Blade Runner: corporate capitalism and synthetic consciousness. Brazil: bureaucracy. Snowpiercer: climate engineering combined with class. 1984: surveillance and language. Gattaca: genetic determinism.
The films that don't work in the genre tend to be the ones that try to summarise multiple anxieties without committing to one. The single-conceit dystopia is the structurally cleaner choice.