Your friend sounds like he or she is on a different (or nonexistent) op-sec plane. A fellow student in my masters program reprimanded me for not knowing my email password to log into my student account on one of our school library computers. She seemed not to understand the importance if a password manager, and that my school email password lived there, not in my memory, and she was more confused when I told her the approximate length and complexity of my password.

Secure habits like this are as essential as eating only animal products for optimal health.

The important thing that people need to know about you is that you are a disgusting shitcoiner, bad actor and evil manipulator and scammer.

The half of the threat model no tool patches: your privacy is capped by the leakiest channel anyone who knows your plans will use. The secure app protected the message in transit. The email copied it into a provider index, backups, and every device it syncs to, outliving the trip it described. Counterparty hygiene is the unsolved problem, not the crypto. How do you raise a friend's habits without turning it into a lecture?

Not so 31337 😹