Because the huge majority of my friends would not consider paying for a social network.
Many have noticed that Facebook provides a lot less value than it used to. They no longer use it to stay in touch with friends but rather to share random news/opinion articles. It would be hard to convince them that what's ruining Facebook is ads and that if they would pay those problems would go away.
The equivalent for regular social sites would be in my mind a service that blocks tracking/user data collection ads etc. - essentially everything people are worried about for a price. If you don't pay the price, you get the 'basic' model where they make money off you by other means.
I did pay for app.net when it started, so I know that I really would pay for it. App.net had a theory that if you made an elite social network, interesting people would pay to be on it, and then everyone else would follow.
In practice it seems these don't really work, when there are free alternatives.
On the other hand, the public social networks are becoming too abusive for many subgroups so maybe that would be a place to start.
Two simple examples:
- Dynamite Circle
- Mastermind Talks
Note that these are not open networks, and they are focused on creating opportunities for members to generate lots of value (both monetary and otherwise).
My siblings and I communicate privately through Google+ circles. None of the photos, posts, etc are published to the broader world ever. Unfortunately, Google Plus has been on its death bed and won't be what we can use forever.
- I never thought I would pay for movies before Netflix.