You first have to determine that code in the PR was generated by LLM(s). How do you do that? What about false positives?

I don't think you realize how painfully obvious it is when people submit LLM generated crap. Most of the time, they literally admit it as soon as you ask, or, concurrently with the submission.

It's a one time tax you pay sure, but after the ban at least you know you'll never deal with that use again. And a lot of these contributions come from the same people.

one of many questions that would have been good to ask before this technology was widely available

Why? If we can't tell the difference...isn't that a good thing?

https://xkcd.com/810/