I've always questioned how much more secure this is than emailing files, for outbound documents. It limits the opportunity window of an attacker when the first document is sent, rather than the file sitting on various mail servers. But if an attacker can intercept the email, then that attacker can sign in to Nextcloud and access the file. Ideally, you would do some sort of identity proofing or non-email communication of initial credentials before exchanging files.
#security #infosec