If our running a business you use windows. Maybe you have a single task oriented server somewhere that you can dedicate to linux. Maybe you have a few of these. But for the business (clients and general personnel) as a whole, you are using Windows.
For most Freepers Windows is just fine. Don’t be scared out of it.
As a cyber security professional and penetration tester, I use Linux for my personal machine, and two of my corp machines. My company also issues one windows laptop.
All of my important stuff goes on the Linux server. But I seriously hope that corporations continue to use windows. It keeps me employed and makes my job far easier.