[packeted]

Why does Facebook need to give up any of this information to developers in the first place? Presumably these apps are part of the reason Facebook has the engagement it has? Or part of the reason for the user growth it has seen in the past?

Perhaps this will prompt Facebook to start cutting out third party developers and build more home grown social apps, leveraging the data it already has on what eye balls engage with. Maybe they'll only grant API access to large companies, eg. TripAdvisor, who they can hold accountable and would be worth investing the time to audit. Perhaps they will start their own internal Cambridge Analytica where no data sharing is even necessary, assuming they haven't already.

[underwater]

That’s answered in the post. It was a vision of socially enabled third party apps that never eventuated. They cut they feature when it turned out that no one really needed the data for legitimate reasons.