The word "dimwit" is used to describe someone who is not very smart or clever. It means they have a lack of intelligence or understanding. Full definition
This small group of dimwits holds the fate of humanity in their hands and too bad for us, they are very intoxicated. (nerdlocker.com)
Ever rising IQ scores suggest that future generations will make us seem like dimwits in comparison (scientificamerican.com)
But right now, it's only precommitted utter dimwits like Fanny and those (like the IPCC itself) primarily motivated by the ideology of governmental expansionism, who profess any trust in the IPCC. (judithcurry.com)