Law is founded on the idea that reality matters and just making stuff up won't work there. If you could just hallucinate things and run with that there would be no reason for law because it wouldn't matter whether anything was true.
The whole point of the legal profession is stretching the truth to the furthest extent towards your aims while remaining nominally within a given framework. LLM's are very good at that and are becoming increasingly good at that, and will be better at humans than that in the near future (if they aren't already)
