Nowadays, a majority of apps require you to sign up with your email or even worse your phone number. If you have a phone number attached to your name, meaning you went to a cell service/phone provider, and you gave them your ID, then no matter what app you use, no matter how private it says it is, it is not private. There is NO exception to this. Your identity is instantly tied to that account.
Signal is not private. I recommend Simplex or another peer to peer onion messaging app. They don’t require email or phone number. So as long as you protect your IP you are anonymous
Why is only message text considered “information / content / context” here. Signal has your real name and address via phone numbers, and has every other real person you talked to, and when. Why is “message text” considered context, but social networking graphs aren’t?
All these definitions are highly subjective, and the above one clearly considers social networking graphs to not be “content”. Basically they’ve re-defined privacy in a way that excludes highly sensitive information like everyone you talk to, and when.