This paper is a little bit of a red herring, as Yannic, an NLP PhD, covered well here:
https://www.youtube.com/watch?v=aX8phGhG8VQ They filtered questions that GPT-3 - the model they tested - got right before constructing the dataset. They asked questions about common misconceptions, conspiracy theories and things humans have believed until recently. The dataset should be called expert consensus vs public entertainment belief i.e. they consider the ground truth as a humourless experts answer, while the reality is in a random sitcom, you -would- expect the meaning derived by the these models (the meaning more common in the training data... such as what happens when a mirror breaks).
It's also clear that RHLF models can be given instructions to reduce this issue. And in many production LLM models, something called few shot is used - in context learning - where you provide several examples and then ask for a new case. The accuracy is again improved this way, because the model "deduces" that you are being serious and humourless, when asking about mirrors breaking, and are not asking in the context of a story.
It's also one of the only datasets that fails to increase with scale (There was a big, cash-paying high incentive challenge to find other datasets, and it pretty much didn't find any that can't be worked around or are not experienced by RLHF models like ChatGPT). So it doesn't represent a wider trend of truthfulness above human accuracy being impossible (dated/data drift on the other hand, clearly remains an issue).