Agreed, the article misleadingly suggests a "why" that it never provides, it merely determines that the prejudice exists.
So... let's speculate on why.
My observation over the last several national elections is this: people often look for quick decisiveness as a proxy for this quality called leadership. They're less likely to spot the fraud as the IQ of the leader increases, because the decisions made by lower-IQ leaders are more obviously flawed and ordinary people can notice.
As IQ increases beyond 120, the presentation of quick decisiveness begins to decrease, as the higher-IQ leaders realize that there are more factors/consequences involved in their decisions. So they seek out more information, more voices, and appear to be dissembling and ineffective. They make better decisions, and are punished for it.
