It's funny, people have all sorts of worries about how the world might end if AI chooses it to. But if AI was smart - it would create a new social network, and really ramp up the engagement factor. The reality is we do get physically addicted - we do need that dopamine hit. If AI created "the perfect" social network, we would all be far too busy screaming at each other online, to notice the world dying around us.
...or did AI already do that? cue X-Files music