I doubt there is a comparable correctness metric between LLMs and protein structure prediction models.

You can measure how many times they correctly predict a thing, but results will greatly change according to what your objective is. Those are only comparable when you're trying to predict the same thing.

As such my reply would be: sometimes more incorrect sometimes more correct. However, in general, a mishandled incorrect protein structure prediction is way more expensive than an LLM hallucination.