In the envisioned 2021 of Johnny Mnemonic, Earth has become a hyper-connected, corporate-owned wasteland where the primary currency is information. Society is fractured between high-tech corporate enclaves and the "Lo-Teks," a resistance movement living in the ruins of the old world. The environment is depicted as grim and urbanized, with technology integrated into every facet of human biology and social interaction, leading to a world that is literally sick from its own advancements.

The central societal dynamic is the existence of Nerve Attenuation Syndrome (NAS), also known as "the black shakes." This film-exclusive addition to the William Gibson story portrays a global pandemic caused by overexposure to the electromagnetic radiation of omnipresent technology. While the film presents a divergent timeline where the internet evolved into a tactile, 3D virtual reality landscape, its depiction of a world ravaged by a plague while pharmaceutical giants withhold a cure resonates with modern critiques of corporate healthcare power.

Technologically, the film’s most famous prediction is the neural implant used for data storage. While we do not use human brains as hard drives, the prediction of information overload has become a psychological reality in the 21st century. The film also successfully anticipated the ubiquity of video calling, the rise of global hacking collectives, and the concept of deep-fakes used for identity theft. However, its vision of 2021 hardware—bulky VR headsets and physical data ports—remains firmly rooted in 1990s industrial design aesthetics.