Website operators are being asked to feed LLM crawlers poisoned data by a project called Poison Fountain.
The project page links to URLs which provide a practically endless stream of poisoned training data. They have determined that this approach is very effective at ultimately sabotaging the quality and accuracy of AI which has been trained on it.
Small quantities of poisoned training data can significantly damage a language model.
The page also gives suggestions on how to put the provided resources to use.
I am proposing neither of those things.
The way to effectively use this is to detect scraping through established means and, instead of banning them, altering the output to feed the target poisoned data instead of/in addition to the real content.
Banning a target gives them information about when they were detected and allows them to alter their profile to avoid that. If they’re never banned then they lose that information and also they now have to deploy additional resources to attempt to detect and remove poisoned data.
Either way, it causes the adversary to spend a lot of resources at very little cost to you.
I have no idea what “established means” would be. In the particular case of the Fediverse it seems impossible, you can just set up your own instance specifically intended for harvesting comments and use that. The Fediverse is designed specifically to publish its data for others to use in an open manner.