X's AI training on user tweets is set to become mandatory, with changes going into effect Nov. 15. Users will no longer have the option to opt out of having their posts used for AI training. The change comes as tech companies increasingly rely on user data to train and improve AI models.

Source: https://www.cnet.com/tech/services-and-software/x-is-using-your-tweets-to-train-its-ai-heres-how-to-disable-that/#ftag=CAD590a51e