I don't think so. First of all, if a lawyer thinks that I have a strong case, they could agree to be paid after I win, so I don't need to pay out of pocket up front. Second, it is easy to prove that an AI company used my pictures, since they would need to download the pictures to train on them. Alternatively, if a platform sells it to the AI company, there is a record that it was sold for the purposes of AI training.(In that case, we don't have to prove that the image was used for training, since the crime is the sale.) Lastly, since the license and purchase info is contained within the metadata of the picture, they can't argue that the license was unavailable or something. They have it right there in their servers!