That is not to say that everything was bad. Users liked working with Linux Mint (still my fav distro), RocketChat and NextCloud were popular as well. Zimbra as a mailserver was ok, there were a few complaints about the scheduling tool. Jitsi worked well, at times. I'm trying to remember the other apps that we used.
We had in-house servers with I believe Proxmox and Ubuntu vm's on top, managed by Ansible. That all worked really well. One or 2 Windows VM's for legacy apps.