NIP17 groups are the only space in Nostr where this is code red. Both technically and socially. Technically other Nostr kinds are more transparent, have *some* exposed metadata handles, are not fanned out one by one, etc. But most importantly socially. Few people are going to get conned or socially engineered in kind1 threads or discord style NIP28 chats or whatever else. A closed Signal-style chat group, and one boasting best-in-class privacy, is a totally different risk space. If you're an attacker looking to expose this nostr gaslighting quirk, then NIP17 groups are straight where you'd head.