My plan is/was to structure the payments as a single annual payment that only one person in a group or family needs to pay. Then all the members of the group/family join free. That way you only need to convince one person in a group its worth the change.
I can't see why wouldn't it work. You definitely have some options. Group or family subscriptions is one. Then you can have extra charges for people for example that post above the average (it would make sense to extra charge those who abuse posting). If someone is unable to pay for some reason don't cancel the account(s) simply make those read-only. So even if they don't pay they are not excluded. Bear in mind that people pay for lots of subscriptions! Streaming services, newspapers, vpns, etc. So again if is setup as a profitable but not greedy profit business it should work. One of the key things is convincing people why using a non-manipulative social network is a way better choice than the "free" options. I'm not very good with business ideas but I do believe that there's absolutely room for a healthy social network out there.
