I think that when people (hopefully all of us on this website) work to eliminate ableist language from their vocabulary, they end up with many fewer words to describe certain patterns/behaviors negatively.
Put your favorite non-ableist insult/descriptor in the comments!
credulous, rube, buffoon, lib, debate-pervert, blood-mouth, corpse-eater, bootlicker, settler, cop, settler-brained, fact-resistant, in german there is “denkfaul”, someone who is too lazy to think. It’s precisely avoiding calling someone too stupid to understand something, but instead asserts that they do have the capacity to understand something but that they’re choosing not to, by deliberately not thinking about it. I don’t know of a good english word for it though.
Willful ignorance would be what I would use to describe that in English.
“Willful ignorance” doesn’t have the same sting though. At least to me, because sometimes ignorance is bliss and I choose to stay ignorant on a topic, like e.g. the details of a massacre, to not spiral into doom and gloom.
Calling someone lazy though, in this protestant brained western world, is pretty offensive.
Like some lib going: “wow you tankies are abolutely incoherent” would be a prime target along the lines of “you haven’t enganged with anything I said but instead dismiss it all as ‘incoherent’ because you’re denkfaul”.
Side track comment about language difference
The language difference is so interesting, because the word “stupid” for example would be translated as “tyhmä” in Finnish, but the Finnish word doesn’t carry a similar ableist meaning and isn’t in any way tied to psych jargon for example. The root of the word has ties to words that can be seen ableist however, like “dumm”.
But the word itself could be meaning-translated as “unaware”/“unknowledgeable” and that would probably be the closest to its meaning today.