OK, but back to the regex. That's just pattern matching, and ML/AI has been shown to be amazing at pattern matching (albeit underwhelming at most other tasks). I would trust an AI/ML generated regex, but only because such structures are easily testable. This tool from the University of Trieste has probably been around for 10+ years--probably only 1e3 parameters, not 1e10.
The tool you linked uses a GA (not a NN) to find a short regex that gives correct answers to whatever testcases you provide. If your test cases are correct, it is guaranteed to produce correct output.
GPT-3 is known to be confidently wrong at things like basic arithmetic, so I really wouldn't trust it in scenarios like this. Maybe one day I'll be able to trust NN-generated code without testing it first, but we're not there yet.
http://regex.inginf.units.it/