"as far back as needed" may be single site multi-user systems. messaging on those systems was a hack that quickly grew important to those using it; but the idea

"as far back as needed" may be single site multi-user systems. messaging on those systems was a hack that quickly grew important to those using it; but the idea of "computers as communications media" instead of machines to perform "thought assistance" tasks for individuals took a while to catch hold. I'd be happy to old fart at ya from my memories of BBS times to slashdot, email me or start a Discord perhaps.