@schestowitz email has been unsafe forever; is being misused; use should be reduced to a local scope notification system; I see no reason xmpp, matrix and other such protocols cannot supersede.
Email is still the most popular communication protocol still using separate ports for io. DNS is an exception since it is not p2p.
Everything has a beginning. Remember when email was the fresh thing replacing nntp and uucp? I never experienced those. I did see people using them and thought of them as being so "efficient" since the person only needs to wait for a message instead of seeking it.
Linux geeks doing what Linux geeks do...