Unfortunately all subreddit mirror requests to that bot are auto-approved, and there is no subreddit subscriber limit. That means that very large subreddits with already-active Lemmy communities get mirrored. That causes unnecessary duplication and a lot of noise due to frequent posts to the subreddits.
That said, I actually subscribe to a few of that bot's communities for tiny, niche subreddits (like with 5k Reddit subscribers) that I followed. I use it because it will take time for Lemmy to reach adoption capable of sustaining those very specialized communities. It's useful for links (less so for discussions.)
Bot Account: Enable this if you are using a script or program to create posts automatically
So a bot account that doesn't self-report would be a violation of policy and should be banned from the entire instance by the admin if discovered.
To be clear: I'm personally not against useful bots. But a “Bot accounts cannot post to this community” mod option would just allow the mods to choose for their community.
First swarming wasps, now spelunking flies. What is going on with insects???