> To be honest, I feel like this is where iOS and Android are failing us. Why is every app allowed to embed a bunch of trackers? Only blocking cross-app tracking on user request as iOS does is not enough (and data of different apps/websites can be correlated externally).

Even if Google and Apple both want to commit to fighting this, it becomes a game of whack-a-mole, because there are all sorts of different ways to track users that the platforms can't control.

As an easy example: every time you share an Instagram post/video/reel, they generate a unique link that is tracked back to you so they can track your social graph by seeing which users end up viewing that link. (TikTok does the same thing, although they at least make it more obvious by showing that in the UI with "____ shared this video with you").