There are many, many bot posts. More so re-posting other highly-upvoted comments from related threads, or re-posting previously posted pictures/videos/links, but bots are certainly farming karma.

I know. I'm still curious about whether there are bots using state of the art text generation or not.

It's hard to be sure. Just as in the (possibly apocryphal) quote from a Yosemite Park Ranger, "There is considerable overlap between the intelligence of the smartest bears and the dumbest tourists" there's considerable overlap between the best text generation bots and the dumbest Redditors.