It doesn't even have to be this convoluted. They can just do what they did with email. Step one, wait until they have the vast majority of users, then due to sp

It doesn't even have to be this convoluted. They can just do what they did with email. Step one, wait until they have the vast majority of users, then due to spam/'problematic' content, algorithmically block the vast majority of other instances from interacting with theirs.