Only an idiot believes all conspiracy theories are real and only a bigger idiot believes all conspiracies aren't.
Here's the thing, there's been far too many proven right to say there isn't merit to investigating them.
Jimmy Savile was named and shamed by David Icke, who was laughed at and labelled a conspiracy loon...by the BBC. Now I'm no lover of Icke, but he was bang on the money, named names and the BBC discredited him. Years later, the BBC was shown to be guilty as sin in the whole thing. Plenty called Icke a conspiracy nut, and even though you can understand why, he was right.
The gulf of Tonkin was proven as factual.
There's some great ones to look into-
The moon landing coverage was fake, not the moon landing itself but it was impossible to film footage and get it through the atmosphere's radiation in that era. I think this one is worth checking out.
Brexit being a money laundering scam. This is so obvious yet some will label it a conspiracy theory and put it in a box with Roswell.
The McCann case. Everything from the disappearance to the shady, shady detective agencies and the money used that went into thin air.