Open Risk on Nostr: securing email with end-to-end encryption is entirely possible so that sounds a bit ...

securing email with end-to-end encryption is entirely possible https://www.openpgp.org/ so that sounds a bit weak as an argument not to have such a capability.

The more important point is that wide adoption requires interoperability, ideally by propagating "good habbits", but (when appropriate) also being pragmatic...