Just having a dedicated port for TLS-wrapped version of the protocol wouldn't help here. HTTPS has 443, yet we still need HSTS to enforce it. That said, dedica

Just having a dedicated port for TLS-wrapped version of the protocol wouldn't help here. HTTPS has 443, yet we still need HSTS to enforce it. That said, dedicated SMTPS port would still be beneficial by cutting down at least 2 RTTs (HELO/EHLO + STARTTLS) from overall transaction time.