I tried Nextdoor but quickly closed the app when it was filled with rumors about who in the neighborhood isn't cleaning up after their dog. Maybe I'm throwing away the baby with the bath water, but I don't feel like I miss out on all that much by forgoing yet another social media platform vying for my attention
I gave it up during the run up to the election. Felt way better off afterwards.
In the meantime, they can create more focused discussion and topics than being open-ended. Lost pets, local handymen (and women), and new shops or dining seem to be the most harmonious.
Sadly, crime reports will get comments about legality of shooting one-another, and discussions end poorly. They should turn off comments for those reports.