This seems legit and I plan to try when I get back to my computer.
“11 steps to keep Meta from stealing your data to train AI: You only have until June 26, 2024 to say no to Meta taking your personal photos and words and using them to train their generative AI. Here are step-by-step directions for opting out.”
https://deborahcopaken.substack.com/p/11-steps-to-opt-out-of-metas-data