Here's a prototype preview of NIP-29 for simple public chat groups:
https://chat29.pages.dev/groups.fiatjaf.com

You can create a group at https://groups.fiatjaf.com/ and then just paste it on https://chat29.pages.dev/ and it should work.

If you're the group owner you should be able to delete other people's posts and kick people from the group. Other moderation capabilities are not exposed because this is just a proof-of-concept. Async messaging capabilities are not supported in this app either, this is just chat.

Here's the NIP: https://github.com/nostr-protocol/nips/blob/simple-chat-groups/29.md