When I started my career, we used PROFS/OfficeVision to communicate and exchange information. It ran on the VM/CMS mainframe OS, we had 3270 terminals. Looking back, it was surprisingly efficient.
Then came the Personal Computer revolution and people got to run programs and hold data on their own machines. It was chaotic and super messy (still is).
Nowadays the trend is to run "SaaS" on mysterious VMs located somewhere in the "Cloud".
Basically we are back to using mainframe computers.
Instance perso. Principalement en français. Personal instance, mainly in French. Linux, OSS, Santé Mentale, 3615 MaVie.