It’s utter nonsense invented by people for reasons known only to them.
Yep.
Where did that come from? Without a single known fact to add, you're contributing pressure to signal your personal, engrained and inculcated predisposition. You're part of the process of how people--completely devoid of facts--mindlessly get labeled "conspiracy theorist!" for example, by the predominant cultural mindset.
I would encourage people to find evidence if not facts to support their assertions.