I'm a long time lurker on this thread and it's certainly opened my eyes to conspiracy theories I never knew existed (pizzagate - wtaf?) and I find other people's thoughts and opinions so interesting!
One conspiracy theory has always baffled me though - flat earth! I've never understood why some people think this is a thing
I feel like most conspiracy theories are about events where the truth needs to be hidden to protect an individual(s) or government or to gain something (money, power, control etc); there is always an ulterior motive somewhere and someone will always benefit in some way. I can't see an ulterior motive to us being told the earth is round when it's actually flat!