Not just public posts or stories. private group chats between you and your closest contacts. automated AI. no human reviewed it first, got flagged and reported.
I think people just fundamentally do not understand what the word "private"means. If you are sending a message via centralized service (Snapchat, Facebook, Tiktok, e-mail, etc) it is de-facto not private*. Just because the communication is between two people and not publicly viewable to other users doesn't give it any special "privacy" status compared the rest of the platform. The operator owns the platform, they can read anything that you type in or upload.
For a message to be actually private it must be encrypted before it leaves your device and decrypted on the recipient's device, that's it.
*There are some services that provide end to end encryption of messages but they are not the norm. No e-mail is ever private, even services like Proton only keep things encrypted on their own servers, once that e-mail reaches a gmail inbox it is just as readable as any other.