I don't know how common this is in the US, but in Switzerland we have a form of incorporation that's quite common and would match ownership by users, which is q

I don't know how common this is in the US, but in Switzerland we have a form of incorporation that's quite common and would match ownership by users, which is quite different from public ownership: A cooperative ("Genossenschaft"). The biggest retailers, some of thr bigger banks snd insurances as well as lots of shared land ownership works this way. According to Planet Money at least in banking in the Midwest it used to be common in the US. I think this could be attractive for services that can be considered internet infrastructure, like Wikipedia, Twitter and (in an ideal world) even Google. Users gain a lot of value from a platform stopping the growth play and going for stability through pleasing their existing user base and expanding in an 'organic' way to users that want more of the same. I could also see this becoming a common thing for blockchain based services since Ethereum contracts would make this a very easy thing to do.