The George Santos Syndrome

Sure, some are fallible and susceptible to this. As far as a liar is concerned, I think the difference is the ability to adjust when confronted with contradictory evidence. If someone in a position of power and control decides to nuke a country because they believe a zombie plague is rampant there, it is better if they have personality type that's agreeable and conscientious when confronted with evidence that shows otherwise. Ideally they realize they're more susceptible to believing falsehoods than others (the researchers showed that there were differences amongst people), and so the susceptible person removes themselves from a position of power and control.