Many companies use RHEL Workstation to run proprietary GUI applications. The application usually runs on RHEL Servers and uses X11 forwarding to show the GUI on the Workstation.

Running the same OS on the client and on the server makes support much simpler. ISVs may not even support more modern OSs like Fedora or Ubuntu.

Those companies don't need an Office Suite as they have Windows machines that can run Microsoft Office. They just need a Linux desktop environment that is easy to use and stays out of the way when accessing the Workstation through VNC.