The question for me is what if nostr is your only connection with them. Even NIP 44 is not private on the same level as Signal or SimpleX. But it should be safe to send a message saying "do not respond to this, contact me using SimpleX". With the new version, metadata is more hidden, but relays can infer things based on traffic, and account compromise can reveal history. That's not good enough in life or death scenarios.
Discussion
I’d have someone else contact them or contact them from my anon account. My best friend doesn’t even know my anon to protect her.
Sometimes there are codes like emojis etc. I’ll post “I’m eating feta cheese on my main so you know it’s me at 4pm”
TBF Nostr may never be “life or death” secure… people who need this will find a way.
While Nostr should do it’s best to have private DMs and group chats, don’t let perfect be the enemy of “good enough to bring the masses, cause the masses really want private chats … like yesterday” #teamhodlbod
nostr:note1elxw8gts7uwaeysdaehu6mrsf7k7z5m720wxpx6e6akqywllwjyq945kd4
to be fair, both simplex and session both use tor somewhere in the protocol. session uses it pretty deeply. Using tor with nostr would be pretty secure with a separate key to your main forum key, especially if you shared it via simplex or session or so.