What signals are left if these are removed? Is advertising worth it at that point?

Meta Platforms has proposed asking all users in Europe to decide whether they would like to see ads targeted based on how they interact with the company’s apps, such as what videos they watch or posts they share.

And isn’t that first-party data? The kind of thing that’s supposed to fill the cookie-shaped gap all platforms are prepping for?

WSJ: Meta Offers to Seek Consent for Highly Personalized Ads in Europe