While I accept most of the concerns, it's better than your comment suggests. I see some promise for it as a tool for reminding you of a technique or inspiring you to a different approach than you've seen before.
For example, I wrote a comment along the lines of "Find the middle point of two 2D positions stored in x, y vectors" and it came up with two totally different approaches in Ruby - one of which I wouldn't have considered. I did some similar things with SQL, and some people might find huge value in it suggesting regexes, too, because so many devs forget the syntax and a reminder may be all it takes to get out of a jam.
I'm getting old enough now to see where these sorts of prompts will be a game changer, especially when dabbling in languages I'm not very proficient in. For example, I barely know any Python, so I just created a simple list of numbers, wrote a "Sort the numbers into reverse order" comment, and it immediately gave me the right syntax that I'd otherwise have had to Google, taking much longer.
Maybe to alleviate the concerns it could be sandboxed into a search engine or a separate app of its own rather than sitting constantly in my main editor - I would find that a fair compromise which would still provide value but require users to engage in more reflection as to what they're using (at least to a level that they would with using SO answers, say).