IVPN on Nostr on Nostr: Let's assume we have some product ideas for IVPN customers to test, invite-only. We ...

Let's assume we have some product ideas for IVPN customers to test, invite-only.
We start a chat community to get feedback and offer a place to discuss our service, privacy etc.

Which platform would you prefer?
- Needs to support multiple channels
- Ideally self-hosted
- Discord and Telegram are no-go due to privacy policies

Options:
- Matrix
- IRC
- Nostr based solution which we have not heard about
- Something else