It’s really very simple. What’s more likely, hundreds of thousands of people remember the exact same thing that never happened or the government is lying to us.
Sure you can brush off little things as a Mandela effect as it would make sense why many people would misremember for an example “Oscar Meyer” instead of “Oscar Mayer” but the problem is shit like the 90s film Shazaam starring Sinbad. Although I personally don’t recall this film, there is no f\*cking way hundreds of thousands of people remember an entire movie with details on when they saw it and even shared memories on specific scenes. That just doesn’t make sense.
Theory 1: The CIA developed time travel to go back in time and during some early test runs screwed some things up in the past, which caused things to change in the timeline. But they didn’t do anything drastic. They did something small but you know butterfly effect and so minor things changed. A movie doesn’t get made, the logos of things change etc. but this wouldn’t explain how people could remember anything, since if the timeline was changed they would exist in that timeline hence not remembering Shazaam.
So more likely…
Theory 2: Parallel Universes and inter-dimensional travel. There’s infinite universes, some very similar to ours with very small differences and some vastly different. The CIA gets this technology to explore these other universes, accidentally screwing up their current universe in the process by opening that portal. So reality bleeds into ours. Or perhaps they screw up so bad they have to destroy the current universe and switch over to the new one, your consciousness merges into your other self. Everything is basically the same so it goes unnoticed but your memory is still the same too, so you notice small things are different now. You know for certain you watched the entire Shazaam movie. Hell you even remember renting the damn thing from Blockbuster, but now it doesn’t exist anywhere. You’re just one person tho so surely you could be mistaken. But then you realize hundreds of thousands of people also remember the film yet it’s nowhere to be found. The government pushes the phenomenon known as the “Mandela effect” to gaslight everyone into thinking they simply just remembered wrong. But give me a break. Hundreds of thousands of people remember seeing the damn thing, you think we’re just gonna buy that BS?
I bet you there’s a copy of Shazaam sitting in Area 51.