Although the data may not immediately identify you, in theory it can be used to recognize someone using devious means, such as applications installed by them or traveling with the same person.
The problem is not only that applications overload data, but also that they can violate the rules of confidentiality of the EU GDPR, collecting information without consent and potentially identifying users. You can not lay the blame solely on the legs of Facebook or the developers, however. The corresponding Facebook development kit did not provide the opportunity to request permission until the GDPR came into force. The social network has indeed developed a fix, but it is not clear whether it works or that the developers implement it correctly. According to the study, many applications still used older versions of the developer kit. Skyscanner noted that he "did not know" that he was sending data without permission.
Facebook expressed sympathy for the concerns of Privacy International, stating that it is important for people to know when an application sends data, and to “control” whether this data is associated with it. Future changes, such as Clean History, will also help, Facebook said. The company also emphasized Financial Times that developers can turn off automatic data collection and can postpone sending application analytics. However, it is obvious that the creators of the applications either do not pay attention to these changes or do not bother to accept them – they may need to push them if they are going to avoid EU disputes and fines.