If there was an ancient high-tech civilization on Mars, it might be too distressing to reveal that to the public. What if there was an ancient war in the heavens, or an asteroid or meteor crashed into Mars?
Even with the Earth being well over 4 billion years old, how many hightech civilizations could have risen & fallen over the past billion years? A combination of world wars & natural disasters could have easily erased any evidence that humanity might have made the climb from the stone age to the space age more than once.
Indeed, if any habitable world occasionally is wiped clean like a writing slate, an Etch_A_Sketch, or a Blackboard, who would know?
https://realsimgear.com/blogs/news/how-to-choose-the-best-monitor-for-flight-simulation
The protagonist in The_Truman_Show gradually starts to realize that his whole life is in something like a GIANT sound_stage. Fortunately, he kept noticing things & connected the dots to see a larger pictuer & world. https://www.scientificamerican.com/article/ai-will-turn-our-lives-into-the-truman-show/
The Paradise TV series isn't about people being trapped inside a GIANT sound_stage. The people know that they are in a HUGE underground bunker, which is set up like a town.
https://en.wikipedia.org/wiki/The_Truman_Show#Plot
https://en.wikipedia.org/wiki/Paradise_(2025_TV_series)#Premise
The opening scene in the Contact movie is spectacular in scale.
The ending of the Men_in_Black movie provides an interesting depiction that each universe is like a data-storage marble being put into a bag with others.
It might be too much for most people to think of the known universe as being like someone's planetarium or cosmic simulation.
The Known Universe by AMNH https://www.youtube.com/watch?v=17jymDn0W6U
Powers of Ten™ (1977) https://www.youtube.com/watch?v=0fKBhvDjuy0 The detail of how big & small things are, goes beyond human comprehension.
