> having them cease to exist without any warning most definitely won't make the world better off.
It may indirectly, in that it may spur a transition to another platform. Most likely, that platform will also be a privacy-invading centralized service, but in an ideal world it would be something like XMPP, Matrix, etc.
People would be using telegram or signal for business in less than one day.
Nobody would ever think about WhatsApp in one month. People that uses Facebook as their photo album would be pissed with losing some old photos taken with digital point and shoot cameras.
Stalkers of former boyfriends and girlfriends would be inconsolable for a few weeks but then move on and be better with it.
There would be a great cultural loss in the disappearance of some groups and even some profiles of very interesting people. But they would resurface, in blogs, telegram channels, forums and whatever else appeared to fill the vacuum.
Nobody misses myspace.
Nobody would miss Facebook.
And eventually Facebook will disappear.
It may indirectly, in that it may spur a transition to another platform. Most likely, that platform will also be a privacy-invading centralized service, but in an ideal world it would be something like XMPP, Matrix, etc.