You’re not wrong. It’s not the same as voting for a desired outcome and if owners/admins push for something, they can usually get it until people leave.
But the system is open source so they can’t just shape their server how they like. They can’t keep others from getting news from outside and they also can’t push their own agenda imo.
So I‘d say you‘re right, it’s not „democracy“ but its either something else entirely or it is „about democracy“. Maybe power equality through federation?