So, I run a company called https://www.localhalo.com/ it builds local communities a bit like discord/slack but all geo-fenced.
We found that social utility is how you solve a LOT of these issues. If someone is going to be negative on your platform then give them the 'action' instead for that pain.
In local this is normally an issue with a neighbour, something for the HOA or something for Local Gov't. Just make them slackbot-esque buttons/commands. Give reacting features for others to support and you've turned decenters into your most active patrons.
The trick with social utility is only giving access to solutions that better everyone. People are lazy and if they can find a single way to do 80/20 of their community wants it normally produces good-actors.
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