they'll end up preying on the people in 3rd world countries that don't have strong privacy legislation. Same way as Phillip Morris did with cigarettes...
A similar example is sending garbage to China. At a certain point China stopped accepting it. Hopefully soon others will do the same and recycling will be tackled correctly.
The network effects has its limits. Messengers and social media platforms have so far resisted a winner-takes-all situation. Since social networks are still more often than not rooted within geographical boundaries, it's possible for competitors to coexist on a global level.
A similar example is sending garbage to China. At a certain point China stopped accepting it. Hopefully soon others will do the same and recycling will be tackled correctly.