It probably depends upon where you're looking. I never go to the front page, or even mildly popular subreddits for that matter. Ignoring the bot used for moderation, I would be surprised if 1% of the traffic on the subreddits I visit is generated by bots. It wouldn't surprise me if most of Reddit was like that, but you won't hear about them since they aren't the focus of everyone's attention.

Most bots on reddit are too cheap to use LLMs, from when I moderated most seemed to just have harvested a bunch of old comments and links that they reposted.

how are they built, farmed ? residential proxies ?