That margin just needs to be lower with LLMs than it is with only humans. In a lot of fields, that's a low bar. For example, medical professionals make a shocking amount of mistakes in aggregate.

Sure, but the average LLM makes a shocking number of mistakes in a single conversation.

BTW the medical professional mistake rate is often reported per-patient, not per-decision. That is, of the dozens of things recorded on each patient's chart, one being wrong counts the same as all of them being wrong. It's an easy way to inflate a negligible error rate into one that scares readers.