I don't think licensing issues are important in this context. I have never gotten code from an LLM system that wasn't something I would create myself if I taken

I don't think licensing issues are important in this context. I have never gotten code from an LLM system that wasn't something I would create myself if I taken the time to write it manually. You should be thinking of LLM coding assistance as a junior programmer working for you with all of the pluses and minuses. If someone claims they found code from open source project in the output of an LLM, it is most likely the result of over constraining the specification i.e. I want you to make me painting that looks just like the Mona Lisa.