It's not really even technical garbage. From many throwaway lines it's clear that the writers actually knew their stuff. They just chose to not make a hacking movie based on realism (because boring) but based on the zeitgeist, the computer tropes of the 80s and early 90s, and the concept of "cyberspace" as envisioned by Gibson and made its way to the collective consciousness. In a time when virtual reality and 3D graphics were at peak cool, yet most people had no experience with computer networks, or even computers at all.

"Cyberspace […] A graphic representation of data abstracted from the banks of every computer in the human system. Unthinkable complexity. Lines of light ranged in the nonspace of the mind, clusters and constellations of data. Like city lights, receding." – Neuromancer