It would mean back in 1993 we would presume the show was going on for years and years more and right before we left, threw this hidden monkey wrench in for all our successors.
In the April 1993 episode, "So It’s Come To This: A Simpsons Clip Show," Homer goes into a coma after being blown up by Bart's April Fools' Day prank. The theory, proposed on Reddit by Hardtopickaname, stated that Homer never recovered and the whole show was happening in his head. Evidence included the more fantastical plots that came after the episode and the fact that all the characters remain the same age.
Though the theory gained a lot of positive feedback and traction online, it has now obviously been disproven. In addition, Jean also debunked the "Dead Bart" theory, which claims a "Simpsons" episode where Bart dies was produced and locked away, saying both bits of speculation go in the "intriguing but false file."
The good news is there are still plenty of "Simpsons" theories out there for everyone to get excited about. For instance, did you know every member of the Simpson family is a genius? It's true! You know, maybe ...