Metadata doesn’t work that way. I can create a fake photo in Midjourney or Dall-E, upload it to Twitter, and it isn’t going to have any metadata identifying it as AI-generated. The only traceable info is my account and IP address. Am I an AI or a human? Who knows?
There actually are some methods that could identify AI-created text, images, and videos using embedded “token” elements that are given slightly higher priority than other elements, and are rotated on a regular basis. A date and time match on the uploaded content vs. the tokens prioritized at a certain time could help identify that the content is AI-generated.
But this requires cooperation of the companies offering the AI product, and everyone would have to be on board. That won’t happen, because this stuff is getting so good that you won’t need giant server farms run by OpenAI or Google. Smaller programs without the tagged tokens will run on anyone’s computer or phone.