It was one of the very first movies about the topic (1983), and yet it balances being an entertaining blockbuster with very realistic depictions of many kinds of hacking, from waiting around for a port-scanner, to patiently shoulder surfing an administrator, to dumpster diving and just doing research on your opponents, plus many others. It even bases the overall plot on AI-training-set-poisoning! To this day that topic remains pretty far out of the public consciousness as a concern, but it's probably gonna be a pretty big deal.
It also captures a core hacker cultural feeling of "curious grey-hat teenagers having fun exploring" versus "large powerful entities getting very mad at the wrong people over their own failures to implement basic security safeguards."
It even manages to stuff a nuclear deproliferation + broad antiwar morality play in there, and through all of this, there's not a single crazy imaginary hacking visualization! It's a great hacker movie.