Huh, the moderation issues are one problem with it and now when you put it that way, sounds an awful lot like the moderation system of reddit. And we know how great that is. /s
No such alternative exists on NextDoor. Don't like the content or moderators? Your only choice is stop participating. I have no idea why NextDoor thinks that is good for their business model. Over time the site will just be populated with Karens.