I actually started working remotely 50% of the time in 1999, when virtually no one was doing it. One week at home, next week in the office. That quickly evolved to all at home except a few days each month in the office. By 2005 or so, I went to the office a day or two just a couple times a year.
Initially we had some sort of conferencing "system" that I do not even recall the name of. It was a real pain in the ass, so I seldom used it. Some of us had clunky old cameras clamped on to our monitors; the office had a conference room with cameras. I found conference telephone calls, with concurrently transmitted emails for documents worked just as well.
At some point we used "Google Go to Meeting" (is that the right name??), also something from Microsoft I think, and then Skype. There were others, too. My work didn't require me to use it more than a few times a week. I use Zoom now much more than I ever used the others, more for family/personal reasons than for business/volunteer purposes.
What I was an early, very heavy user of was voice recognition software, probably because my typing is poor and dictating/transcription was cumbersome working remotely. For a short time I emailed audio files to my support staff for transcription, but it took forever to send even just an hour or so of dictation. I became a very early user of Dragon Naturally Speaking, when it only worked well if you paused after each word. That quickly improved. Found it to be fantastic.