Copied from an old comment of mine:

Re: bots

If feasible, I think the best option would be an instance that functions similarly to how Reddit’s now defunct r/BotDefense operated and instances which want to filter out bots would federate with that. Essentially, if there is an account that is suspect of being a bot, users could submit that account to this bot defense server and an automated system would flag obvious bots whereas less obvious bots would have to be inspected manually by informed admins/mods of the server. This flagging would signal to the federated servers to ban these suspect/confirmed bot accounts. This instance would also be able to flag when a particular server is being overrun by bots and advise other servers to temporarily defederate.

If you are hosting a Lemmy instance, I suggest requiring new accounts to provide an email address and pass a captcha. I’m not informed enough with the security side of things to suggest more, but https://lemmy.world/c/selfhosted or the admins of large instances may be able to provide more insight for security.

If possible, an improved search function for Lemmy, or cross-media content in general, would be helpful. Since this medium still has a relatively small userbase, most bot and spam content is lifted from other sites. Being able to track where bots’ content is coming from is extremely helpful to conclude that there is no human curating their posts. This is why I’m wary of seemingly real users on Lemmy who do binge spam memes or other non-OC. Being able to search for a string of text, search for image sources/matching images, being able to search for strings of text within an image, and being able to find original texts that a bot has rephrased are on my wishlist.

Re: AI content

AFAIK, the best option is just to have instance/community rules against it if you’re concerned about it.

The best defense against both is education and critical examination of what you see online.

There are some other helpful comments on that post as well.