> I remember the paper proving that hallucinations could never be fully solved back in 2024

The papers that use the halting problem or the Gödel's incompleteness theorem to prove something about LLMs are dime a dozen. The problem is they prove their results for any computable system. You need to also believe that the human brain contains "magic" to think that humans are exempt.

I believe I've said the same at the time this paper was published. There is no need for hindsight to notice the problem.

The required amount of compute and training data and whether the existing training methods were up to the task had the real potential to be show stoppers though.