I agree here.
Moving to git is one thing, but doesn't going to GitHub put all their code at risk for CoPilot AI mining by Microsoft? (If one considers that a bad thing, which many don't, I guess.)
Your code is AI mined regardless where you put it today I'm afraid to tell.
Unless you put your code in a private repository self hosted behind a login. However, if your code is public. You can bet it will be used for AI training. Again regardless of which platform. And regardless which LLM. So all platforms, all internet, all LLMs.