Are you by any chance from Korea? Cause that hysteria about “fan death” seems to be a prevailing urban myth around there:
https://www.reuters.com/article/world/electric-fans-and-south-koreans-a-deadly-mix-idUSSEO210261/
But apart from people with dust mite allergies and the like, where air circulation can increase the allergen content of the air, sleeping with an fan on does not come with any health risks whatsoever:
https://www.sleepfoundation.org/sleep-faqs/is-sleeping-with-a-fan-on-bad-for-you
Do you mean the stoned ape theory? Never have seen it interpreted in that way, but it’s weirdly comforting and I kinda want to believe it now. Makes humanity feel less lost when there could be some fungi buddies looking after us, secretly manipulating us into becoming better beings.