Interesting. Unlike some other popular image generation training, is there a chance that Meta technically got copyright permission for many/most of the images that were posted to its properties?

I'm thinking: When the user who uploaded the image was also the copyright holder, that might've been covered by an agreement that technically permitted this use by Meta.

(Copyright isn't the only legal issue, though. For example, a person in a photo that someone else uploaded doesn't necessarily lose right to their likeness being used for every purpose to which a generative AI service might be put.)