This would have been pre-1990s. The hero rambles on about the great alien war that humans eventually won. By the time you get to the end of the short story, you realize that the aliens actually won, and to forestall a revolt have kept the Earth in a Matrix-like state of complete unawareness of the true situation. Very creepy - would like to find again - author/title?
"Eight o clock in the morning " by Ray Nelson
Eight O'Clock in the Morning (1963) is a very short science fiction story by Ray Faraday Nelson where the main character, George Nada, is accidentally “woken up” to a new reality of the world ... the reality that has been kept from all humankind.
The question now is: what will he do with that knowledge?
This is an original story with an interesting premise: [What would happen if there were aliens living among us, controlling every aspect of our lives (even the way we perceive reality), and a hypnotist's command to wake up from the trance unexpectedly broke the aliens' spell, too?
The movie They Live (1988) was based on this story