It’s neither. It is wilful ignorance. All those studies sorting political affiliations by education, IQ and whatnot never show a difference that is nearly as large as these kind of comments suggest. There are small trends, but not more.
The average IQ of republicans isn’t much lower. They just choose to squander their potential. Never underestimate the potential often human beings to lie to themselves. It is one of our most honed skills.
Don’t spread false information. Yes orange cats are more likely to be male. No, orange cats are not less intelligent. I’ve just researched it.