Perhaps it's just a bit of observation bias where you see (or at least pay attention to) more of what you're focused on.
Bias or not, an increasing number of people are closing their accounts and leaving social networks but not the social web.
So, what's the difference?
What is social? It is interacting with others, engaging with them in some way, being part of something bigger than just yourself.
Forget about content silos for a moment, but "social networks" are still concentrated in a particular place. We may be able to interact with them in multiple ways and even POSSE our content back to them from outside via gateways and APIs, but the actual network is self-contained.
A network is comprised of nodes and edges (the connections between those nodes) and the activity graph is everything that happens across it.
A social network contains those nodes so, while we may map out our graph, it exists solely within their domain and is therefore owned by the network.
You may be able to export your data but you can't export your graph because the nodes and edges aren't transferable. Well, not without getting everyone to move all at once.
You can still be social without a social network - and by that I mean a centralised one owned by a company.
Of course, you need a social network; even if you only have one friend you still have a network - it is only small with just two nodes but it's still a network in a purely "connected items" sense.
Now, if we choose to map that network then we hold that map. My blog contains posts that are likes or replies while other posts contain links to other people. My directory page lists incoming connections from people who have liked, mentioned or replied to my posts.
It's disorganised but it's still a map, a social graph.
And I hold it.
Just as I have mine other people hold theirs and so on, and they are all sections of a much larger, interdependent network.
The difference is, however, that each section exists in its own space and is not centrally controlled. I will always hold and own my graph, just as you will yours.
We don't need to export or transfer anything because, as long as you remain at the same domain, all the nodes are always available, not locked away behind the walls of someone else's network.
We don't necessarily have the convenience of a centralised network for establishing connections, patterns and friends of friends, but we also don't have a landlord trying to leverage those connections for financial gain while we rent our space within their property.
Discovery may be harder but we can temporarily borrow the graphs of others, following the connections from our own.
We become more discerning when making new connections, adding new nodes, due to the greater investment in finding them. Our graphs become more meaningful, more valuable and more rewarding.
I know which I'd rather pick.