Stackoverflow at least has the benefit of whatever comments might be around it. As far as I can tell, the copilot suggestion doesn't have any way to rate it, make a comment, flag it, etc.
I wonder, how much better could Github Copilot become by also looking that the modifications that are subsequently made to the accepted suggestions? Obviously this would go quite a bit further in terms of telemetry, and may become an issue. They would essentially be training based on non-public code at that point.
That will make it the target of a collaborative bias attack.