> I still completely believe in Facebook as a good product for the world.

Well, people believe the craziest things so you are in good company.

But on the important point on whether facebook is salvageable with a user subscription model: extremely dubious. In some sense adtech has ruined the concept of users paying for a good product and there is poetic justice in that. The magic wand that turns users into product wont turn product into client.

What might work is "social as public or semi-public infrastructure", namely getting cities, companies, states or even countries paying for user accounts of residents, employees etc. as a sort of benefit.

But even in the unlikely scenario facebook would relinquish its residual adtech earnings in favor of a new and less lucrative business model it would likely face stiff competition from newcomers with less historical baggage