I find such replies to be worthless wastes of space on par with "let me google that for you" replies. If I want to know what genAI has to say about something, I can just ask it myself. I'm more interested in what the commenter has to say.

But I don't know that we need any sort of official ban against them. This community is pretty good about downvoting unhelpful comments, and there is a whole spectrum of unhelpful comments that have nothing to do with genAI. It seems impractical to overtly list them all.