@m Delta Chat is never mentioned in any privacy or alternative secure messenger guides. I see Threema mentioned as a Signal alternative, but never Delta Chat. It's kinda mind boggling how the entire internet is wearing blinders.

My only guess is that the security minded folks see "email" and "PGP inside" and immediately says NO, this is not good because we've been trained to think emails can never be secured without looking at the actual implementation details.

It can indeed be secured if everyone is using the same implementation.