>3) Employee training. Back in my days KDE was used (and I believe it still is), but it's different enough from Windows that people need training. And there's 35k of employees, most of which don't have any IT experience outside from their Windows computer at home.

I've been seeing this pushed as a Linux disadvantage for at least 18 years now.

So if employees can't figure out how to switch from WinXP or Win7 to KDE, please explain exactly how they're going to switch to Win8/8.1/10 without any training.

If no one is getting training for Win10, then no one needs training for any Linux DE.