My department just gives them a PDF explaining with cool graphics how Linux can save more money, how more secure it is, how we can avoid the constant force fed bug filled updates that MSFT pushes, how we can customize it exactly to our and users needs, we can actually own our own keys... The goes on and on.

No, because there is no simple point and click group policy/active directory equivalent in Linux that allows a group of 5 IT techs to manage 2000 desktops. And if you get your shit together and actually use the tools that Microsoft provides, you don't get surprise updates, you can image PCs via a gui over network booting, you get bitlocker keys backed up in your domain etc etc etc etc etc.

All the things that allow a business to manage hardware and software with the minimum amount of expensive employees, Microsoft provides it, for money of course. That money is offset by the reduction in IT guys needed to look after everything.

It's that simple. CorporateLand won't touch Linux on the workstation until that's possible.