Imagine you're in a library filled with the world's knowledge. You don't have any context for where anything is, what's real information, fiction, fact, or just ideas.
Now imagine you can search, but only for key words or vague information. But someone you trust, who you don't have any reason to doubt, shows you these books in the legal section. They are complicated, but they do a good job of explaining how they work.

This is basically how any misinformation spreads on the internet. Everyone has the world's knowledge at their finger tips, but not everyone knows how to find what they need. Those people rely of others to help them and are taken advantage of. This may very well have started as a joke, but sovcits have been given this information as fact and convinced that anyone who tells them otherwise is just ignorant or deliberately against them.

I do believe this is compounded by the fact you simply cannot trust anything you read these days. There are no reliable sources and any news you read could very easily be deliberate propaganda or (more likely) just misinformed and framed in a way to get more views.