A pattern is dark if intentional. I would say hallucinations are like CAP theorem, just the way it is. Sycophency is somewhat trained. But not a dark pattern either as it isn't totally intended.
Hallucinations are also trained by the incentive structure: reward for next-token prediction, no penalty for guessing.
Hallucinations are also trained by the incentive structure: reward for next-token prediction, no penalty for guessing.