From my limited understanding, it mostly seems like misattribution of all the very obvious chaos and uncertainty about "grand" events like climate change, economical strife, etc.

It's less that someone holds pancake planet as their sole belief but more a web of interconnected beliefs that would explain the true cause of these nebulous events if they were true.

Not that it makes the outcome any better that people choose a more palatable ideological narrative over reality but there is a part of me that recognizes ignorance would be more blissful.