

There are a lot of modern languages that don’t have a pure “yes”/“no”. Likely, this was not uncommon in history either.
Alternatives to “yes”/“no” in those languages can vary. They generally include methods such as “not (that)” or negating the (sometimes (mis-) implied/interpreted/understood) verb of the question.
This sounds like schizophrenia to me. Particularly the weirdness and occasional paranoia. There’s no agreement on the causes of it, as far as I know. Whether AI can either cause it or push someone over the edge, I have no clue.
My brother has schizophrenia and is one of the most technologically inept people I know - both before the symptoms and currently. It is known to have existed well before modern computers.
Also worth noting that schizophrenia onset usually occurs in adulthood with and average age between late teens and early 30s. Later onset is less common, but known to occur.