I disagree, there will always be conspiracy theories but a conspiracy theory which can point to real life examples is much much more credible and will gain far more followers than one which can't.

People don't all blindly follow every conspiracy theory but if your local politicians have been caught 10 times taking bribes before you'll be more willing to believe that a particular action is due to bribery. If the NSA has been caught spying on people a few times before you'll be more willing to believe they're doing it again.