A nice capability would be to have a MTA available in VyOS so one can send status, notifications etc through SMTP.
A good enough alternative to fullblown sendmail would be to install msmtp which exists as a deb-package in Debian Bookworm.
Compared to using a script which uses netcat (nc) msmtp supports TLS which more and more emailservers prefers.
Ref:
https://forum.vyos.io/t/how-do-i-install-sendemail-on-vyos-1-2-or-another-mechanism-to-send-email/