They don't have a social media service, right? So where do they get the data to train their AI models ? Surely they need a lot, right? It would be nice if the public knew who cooperates with them (other than governments) and just boycott their services, or at least pressure them.
If company X doesn't offer your data to governments officials, but offers them to Palantir which makes a profile of you that it offer to the same officials, isn't that even worse ?
That's not correct. Under the GDPR, the data that Facebook collects on you makes them the Data Controller. Any partners they share data with would be considered Data Processors. When you invoke your right to be forgotten under the GDPR, then both Data Controllers and Data Processors must delete your data. So if Facebook partners isn't deleting your data after you filed a request to Facebook, then they are violating the GDPR.
That said Facebook is certainly violating the GDPR left and right. For example with their "Pay or Consent" model...