> It's unclear to me if the resulting product will be better or worse.
It will be worse. If you want endless streams of synthetic text from an AI, you can already get that, today. What you can't get is a conversation with a human who has first-hand experience... Except via forums like reddit.
Given how trivial it would be for me, an amateur AI tinkerer to make a reddit bot that nobody can tell from a human - with an agenda subversively hidden in contextual responses - I can't imagine that even reddit knows the full scale of its bot problem today.
Not the best link, but this largely sums up an effort by reddit to hire "International Ambassadors" that would create a low-effort alternate language version of subreddits about 2 years ago. A dead comment below yours has somebody's personal-ish experience with the program.
Personally, it's pretty easy to find posts on reddit that pair a vague question with an image. I imagine that there are normal people that could be posting these, but it's such easy engagement bait that's both trivial to create as well as use as cover to recycle old comment threads for karma.
Now, what would be more interesting to know, but Reddit isn't going to tell us is "How many accounts banned for bot behavior use a custom username versus using the default generated username".
The reddit front page has been an absolute dumpster fire of repetitive, ai-generated (or at least content farm generated) rage bait posts since the mod revolt a while back. I wish there were a way to quantify it, but basically all the "generation" subreddits, personal finance subreddits and "am i the asshole"-type subreddits absolutely dominate the front page and /r/popular with rage bait posts.