The article only talks about deployment costs. What about the rest?
For you a company should just throw away it’s employees to hire inexistent Linux experts or people using Linux software or whatever?
There is the server side. There I agree that using Linux is great.
On the client side it can be more complicated. A lot of schools in various domains teach the students how to use the software on windows. Not Linux.
Furthermore, a company doesn’t pop into existence the moment where it thinks it needs to switch to Linux.
The company already exists, providing work to the employees, trained on windows. So switching on Linux may change the software if it cannot be used on Linux (not everything is a saas). And that can be a time consuming process for the employees too because they don’t know how to use it efficiently.