Instead of median, what if the produced output is indistinguishable from the 99th percentile commentor (meaning, "genius" level commentor)? Would it still be valueless? In what sense?
But at a higher level, talking with a bug or robot or rubber duck, no matter how smart it sounds, isn't very valuable. There is no mind to change on the other side of the conversation. There is no life that is being lived on the other side of the screen, the experience is entirely one sided.
The max possible value, imo, is at the level of playing a video game vs a bot. It could be fun, you'll probably improve at the game, and maybe you'll learn something, but more than that? I am deeply skeptical.