I've suggested things like this before. Scrapers grab data to train their models. So feed them poison.

Things like counter factual information, distorted images / audio, mislabeled images, outright falsehoods, false quotations, booby traps (that you can test for after the fact), fake names, fake data, non sequiturs, slanderous statements about people and brands etc.. And choose esoteric subjects to amplify the damage caused to the AI.

You could even have one AI generate the garbage that another ingests and shit out some new links every night until there is an entire corpus of trash for any scraper willing to take it all in. You can then try querying AIs about some of the booby traps and see if it elicits a response - then you could even sue the company stealing content or publicly shame them.