Oddbean

Keychat has implemented a seed phrase using NIP-6. For applications focused on public notes, such as Damus, it is more beneficial for a user to use a single Nostr ID because it can accumulate more reputation. However, for apps focused on private notes like Keychat, using multiple IDs can provide better metadata privacy. A seed phrase allows users to have multiple IDs while only needing to save one seed phrase. Another point is that the double ratchet algorithm used in the Signal protocol is stateful and cannot be used on multiple devices with the same ID simultaneously. The double ratchet algorithm provides enhanced encryption security but sacrifices some multi-device synchronization capabilities. This is an issue that apps focused on public notes do not encounter. https://github.com/nostr-protocol/nips/blob/master/06.md

I believe telling a user not to DM me on this npub that shows their WoT with me or to not DM me on a currently familiar app but to download a new app, create a new account and add a secondary npub for me, is an extremely bad user experience and will lead to scammers harming users. The key is to make Nostr more simple for the masses, not overly complicated. I want a dedicated chat app very badly, but I'm not going to put new users through these hurdles to just DM me. There has to be a better way that has a nice marriage of UX and security.

You're conflating the two & ignoring the nuance nostr:nprofile1qqsth7fr42fyvpjl3rzqclvm7cwves8l8l8lqedgevhlfnamvgyg78spz3mhxue69uhhyetvv9ujuerpd46hxtnfduq3qamnwvaz7tmwdaehgu3wwa5kuegpz4mhxue69uhk2er9dchxummnw3ezumrpdejqj9swg4 just explained. There's a difference in architecture between twitter & telephony. But if folks understand you when you tell them to "DM my cell" I guess it's a non-issue for you.

As I understood from @keychat's evidence.. You need to tell users to Chat with you on Signal but not DM you for Privacy communications.. I guess it is a great starting point to schedule and improving our privacy on private chats..

Honestly while this is a pain, I'm all for it. There needs to be a way for user's to guard their entire chat history in the event an nsec leaks. If a bad actor is just hoovering up my DMs waiting for my nsec to leak, then they may be able to find something from years ago that in any other application would have been able to be deleted. If people shared home addresses or any harmful personal information over a DM it can be vulnerable in time. Private relays help/fix this issue, but not all user's are going to be able to configure one. Until the day comes where messages can be ensured bad actors aren't hoovering them, I will not suggest any user share any personal info over a nostr DM with me! Even with nip44, it's still known what language the user's is likely to be speaking in, and therefor the alphabet, and even intent, which lowers the probability of a brute force ciphertext attack. While that still may be a high number, I don't want to bet on it if it's possible to rid that probability entirely!

To chat with another nostr user, we need to somehow share some information in order to connect, so that when we chat I know it is them and I'm not just picking a random person. If so, it seems that you could associate that information with a known nostr ID in a new event kind or in a metadata field. Maybe you don't want to make this association with ratchet keys or whatever they are called, in order to preserve privacy, but there needs to be something otherwise I'm just chatting to a random person I don't know if it is them. So it seems there could be a way to automate this part for a better UX. But without knowing how keychat works I can't speculate any deeper than that.