The LLMs are generating training data at a faster rate than SO. All the prompts and the responses will eventually be 99.99% of the training data.
You want us to rely on models that are overfit to hallucinated LLM interactions.
* The LLMs have a sufficient "understanding" of the request and of how to write code to fulfill the request
* Have a way to validate the suggestion by actually executing the code (at least during training) and inspecting the output
From what I've seen we are still far away from that, Copilot and GPT-4 seem heavily reliant on very well-commented code and on sources like Stackoverflow
If I were training a code model I'd take a snippet of code, have the existing LLM explain it. Then use the explanation and the snippet for the test data.