Nextdoor is fucked up because either you're in it, or your house is probably the house they all talk about.
When I tried to sign up for it ages ago to check it out, Nextdoor wanted me to provide the email addresses of five people, which would have meant a bunch of knocking on stranger's doors asking for sensitive information. So now I just try to ignore that it exists. They probably use a Facebook group I'm not invited to, anyway, and I do not want to know what any of them think, about anything, ever.