Now "email" is synonymous with "Internet E-mail over SMTP" which was not always the case by any stretch of the imagination. It used to be there were many syste

Now "email" is synonymous with "Internet E-mail over SMTP" which was not always the case by any stretch of the imagination. It used to be there were many systems/protocols and even self-hosted in isolation email systems and bulletin boards. Some still operate to this day, though mostly delivered over the internet, but through different channels than general SMTP internet email. --- That said, email is a better term than matrix, but any other term still wouldn't be the same meaning... "matrix protocol" vs "smtp" might be more narrow/accurate.