Fincher uses this to hold up a mirror to our own lives. We are taught to fill our emotional voids with material possessions.

Tyler was never real. He was a coping mechanism—a projection of the Narrator's suppressed desires and rage. The film brilliantly demonstrates how isolating oneself and leaning into extreme ideologies can cause a person to lose their grip on reality entirely. ⚡ The Verdict: A Masterpiece of Satire

It pushes us to question who we are when we strip away our jobs, our bank accounts, and the clothes we wear. Decades later, that question is just as relevant as ever.