The first thing that comes to mind for me is

https://nextdoor.com/

which is very much about community organizing but it has an aura of "people spreading rumors about bicycle thefts at the movie theater downtown (why don't they call the cops?)", the woman who radiates creepy signs of precarity (is cleaning up and looking for the phone number of the people who are suspected to run an illegal landfill) and then posts screen shots of the creepy come-ons she gets from guys who want to be her sugar daddy, etc.

Maybe there's a space for a platform that specifically targets small, community, in person kinds of organizations, maybe even targeted to a particular geographical area; something like Meetup but just a little less structured.

Here's a fair sized local organization (has more than one run a month) that has a good site

https://fingerlakesrunners.org/

But making that scalable is tricky; somebody in the club's leadership is a Wordpress pro. $5 a month would be cheap, but people are niggardly. If you're a web tech native owning a domain name is table stakes, but I think you'd lose 80% of "normies" even the phone-dependent "internet natives" if they had to get a domain name. There is a certain amount of panic over the breakdown of community organizations, see the line of research described in this film

https://www.rottentomatoes.com/m/join_or_die

and rather than getting $5 a month out of people who think they can't afford it, getting funding from somebody like the United Way (for a particular area) or the Knight Foundation might be a better idea.