My take is that these folks can't accept that nobody is actually driving. It terrifies them to realize that we are all aboard a rudderless ship, so they imagine these secret cabals to be able to sleep at night.
Take COVID. There is insufficient proof that it was the result of lab work, but many many people prefer that warm fuzzy thought over acknowledging that mutating is just what viruses do, and always have done. Knowing that we're all one unlucky mutation away from grisly death is just too much for some folks. "It can't happen again, we shutdown that lab!"
To those people it has to be a nice, neat conspiracy. That way someone is in control, and if we just put those few villains in their place everyone will be safe from viruses, economic instabilty, immigrants, and the boogey man forever.