There's also plenty of people with the brain capacity and breath of knowledge to argue their points logically who chose to instead go around logic with salesmen/politician techniques like appeals to emotion and half-truths because that's just a lot easier than assembling a reasoned and informed argument.

It also allows them to make a point for things which ultimately they want out of some motivation generally deemed as morally bad (greed, selfishness, laziness) without it eventually coming out - say, somebody who finds facemasks uncomfortable to wear and don't really care during an epidemic if they spread it to others, who push the "no face masks" thing as some kind of moral crusade in order to hide their selfish motivations and callousness towards others.

My impression is that this has become increasingly more common in the last couple of decades.