I honestly haven't found hallucination to be a problem on GPT-4 when asking it to analyze or parse a dataset but can acknowledge it being possible (I just haven't encountered it).

I think that if we consider the accuracy rate as measured in various ways being roughly that of a human, then you're trading human mistakes for AI mistakes in exchange for dramatically lower costs and a dramatically higher speed of processing. You might even say a higher level of reasoning. In my own interactions it's been fantastic at reasoning clearly and quickly outside of complex trick questions. Most scenarios in life aren't generally full of trick questions.