Nearly 50 years since Martin Scorsese delivered one of his greatest movies, there are still those looking to have the Taxi Driver ending explained. Taxi Driver builds to a bloody climax and concludes with a cryptic sequences of events — events that may be in Travis Bickle's head. When interpreted literally, the 1976 film ends with a lonely taxi driver, Travis Bickle, saving an adolescent sex worker by killing her pimps, and then becoming a New York City hero who seemingly fulfilled his destiny. However, a closer look implies that Travis' life ends in a figurative hell that he references throughout Taxi Driver.
https://screenrant.com/taxi-driver-ending-travis-bickle-explained/