There's a patreon-like implementation that was just launched. Not sure if that fits your needs? I forget what it's called though... I know nostr:npub1jk9h2jsa8hjmtm9qlcca942473gnyhuynz5rmgve0dlu6hpeazxqc3lqz7 just set one up recently.
There's also a community tab on amythest which I think is similar to reddit? I'm not entirely sure how to use it though. I don't think it's like a private group though?
Sorry, not great answers but I hope it leads you down the right path
nostr:npub18kzz4lkdtc5n729kvfunxuz287uvu9f64ywhjz43ra482t2y5sks0mx5sz creatr.nostr.wine relay
nostr:npub1creatr06r4vr7rzx22f4kawdfj82yt09vw5rqw0kan8sr43h608s3dfeh6
Could dumb this down a step, remove subscriptions. Users pay nostr:npub18kzz4lkdtc5n729kvfunxuz287uvu9f64ywhjz43ra482t2y5sks0mx5sz to start up a private group. Grpstr owners share a URL to invite others?
Boom. Nostr private Groups?
Private groups, generically speaking, should be free! Creatr is trying to serve a different need by helping creators monetize and access control notes and files behind a paywall. Of course nostr:npub13qrrw2h4z52m7jh0spefrwtysl4psfkfv6j4j672se5hkhvtyw7qu0almy if you are interested let me know, but I’m not sure that was your original goal.
I know Coracle recently rolled out a private groups solution but it is quite complex.
